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Thread: Is Momentum or Kinetic Energy Conserved?

  1. #1 Is Momentum or Kinetic Energy Conserved? 
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    The physics books inform us that when two objects with given masses collide, kinetic energy is always conserved.

    This appears to follow the common sense rule that energy is always conserved whichever form it is found in.

    However we are also told that when two objects collide, such as metal balls for
    example, momentum is also conserved. If the two balls are of equal mass then:

    mv(1) + mv(2) = mv(3) + mv(4)

    This equation would balance under the following circumstances: where m = 1kg, v(1) = 5, v(2) = 1, v(3) = 3 and v(4) = 3. Or in other words:

    (1 x 5) + (1 x 1) = (1 x 3) + (1 x 3)

    5 + 1 = 3 + 3

    However if kinetic energy is also to be conserved (K.E. = ½ mv2) then the following equation has also to balance:

    ½ mv(1)2 + ½ mv(2)2 = ½ mv(3)2 + ½ mv(4)2

    Using the exact same values for the variables as used above for conservation of momentum, the equation determining the conservation of kinetic energy DOES NOT balance:

    (1/2 x 1 x 5 x 5) + (1/2 x 1 x 1 x 1) = (1/2 x 1 x 3 x 3) + (1/2 x 1 x 3 x 3)

    (12.5) + (0.5) = (4.5) + (4.5)

    13 = 9 ????????????

    What exactly is wrong here?

    How can both momentum and kinetic energy be conserved at the same time?


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    The physics books inform us that when two objects with given masses collide, kinetic energy is always conserved.

    This isn't the case. Kinetic energy is only conserved in elastic collisions which might occur between atoms, but rarely occur between macroscopic objects. If two macroscopic objects collide, energy is lost in the form of sound and heat and the total kinetic energy after the collision will be less than it was before.

    This equation would balance under the following circumstances: where m = 1kg, v(1) = 5, v(2) = 1, v(3) = 3 and v(4) = 3. Or in other words: ...

    Even in an elastic collision, selecting arbitrary values for the velocities chosen so that momentum is conserved won't guarantee that kinetic energy is conserved. If you imagine a situation in which two balls collide, one of which is initially moving with a speed V and the other is stationary, then if as a result of the collision the one that was moving is brought to rest and the one that was at rest moves off with speed v, then both kinetic energy and momentum would be conserved and the collision would be elastic.


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  4. #3 Re: Is Momentum or Kinetic Energy Conserved? 
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    Quote Originally Posted by galexander
    The physics books inform us that when two objects with given masses collide, kinetic energy is always conserved.
    Only if you categorize the internal energy of the moleculess of the colliding objects as kinetic energy. That is not the usual convention.

    Normally in problems such as you describe the bodies are treated as rigid bodies and kinetic energy is associated with movement of their centers of mass. A collision in which kinetic energy is conserved is called a perfectly elastic collision. If the two bodies "stick together and merge" the collision is called perfectly inelastic, and the "missing" energy is realized as heat.

    In all cases momentum is conserved.

    These two cases can be readily solved. Intermediate cases are much more complicated and require material properties and the theory of elasticity.
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  5. #4 Re: Is Momentum or Kinetic Energy Conserved? 
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    Quote Originally Posted by galexander
    ...Using the exact same values for the variables as used above for conservation of momentum, the equation determining the conservation of kinetic energy DOES NOT balance:

    (1/2 x 1 x 5 x 5) + (1/2 x 1 x 1 x 1) = (1/2 x 1 x 3 x 3) + (1/2 x 1 x 3 x 3)

    (12.5) + (0.5) = (4.5) + (4.5)

    13 = 9 ????????????

    What exactly is wrong here?

    How can both momentum and kinetic energy be conserved at the same time?
    First, I'm obliged to admit that I'm a rank amateur when it comes to physics.

    That said, I believe you're "mixing apples and oranges" here.

    The net momentun of the experiment you propose - assuming a perfectly elastic collision, and using m/s as units for velocity - would be:
    1kg x 5 m/s ---> and <--- 1 kg x 3 m/s, producing a resultant momentum for the system of both metal balls equal to ---> 2 kg-m/s. Please note that momentum is a vector quantity (it has both magnitude and direction).

    The kinetic energy of the system is a different matter. Perhaps the best way for me to explain the experiment you propose is to quote the Wikipedia article on Momentun, which can be found here: http://en.wikipedia.org/wiki/Momentum#In_one_dimension

    "...A common problem in physics that requires the use of this fact is the collision of two particles. Since momentum is always conserved, the sum of the momenta before the collision must equal the sum of the momenta after the collision:



    where u1 and u2 are the velocities before collision, and v1 and v2 are the velocities after collision..."


    Regarding kinetic energy:

    "...A collision between two pool balls is a good example of an almost totally elastic collision, due to their high rigidity; a totally elastic collision exists only in theory, occurring between bodies with mathematically infinite rigidity. In addition to momentum being conserved when the two balls collide, the sum of kinetic energy before a collision must equal the sum of kinetic energy after:



    and

    "...In a head-on collision between two bodies of equal mass (that is, m1 = m2), the final velocities are given by:




    Thus the bodies simply exchange velocities..."


    and,

    "...The kinetic energy of an object (in this case the two-ball system) is related to its momentum by the equation:



    where:

    is momentum and is the mass of the body..."



    In the case of your experiment, the balls would have kinetic energy of (1/2 x 1 x 5 x 5) + (1/2 x 1 x 1 x 1) = (1/2 x 1 x 1 x1) + (1/2 x 1 x 5 x 5). Using the units kg for mass and m/s for velocity gives 13 kg(m/s)=13 kg(m/sec)=13 joules. Notice that the velocities are directly opposing in this experiment. Since they are both squared the resultant product is positive.

    I believe the kinetic energy formula used in your experiment is the Newtonian (classical mechanics) formula. It has magnitude, but no direction. The net momentum of the two-ball system, however, would remain ---> 2 kg-m/s.



    I believe this is how it would work. If I'm mistaken, please feel free to correct me.

    Chris[/tex]
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    Quote Originally Posted by Old Fool
    The physics books inform us that when two objects with given masses collide, kinetic energy is always conserved.

    This isn't the case. Kinetic energy is only conserved in elastic collisions which might occur between atoms, but rarely occur between macroscopic objects. If two macroscopic objects collide, energy is lost in the form of sound and heat and the total kinetic energy after the collision will be less than it was before.

    This equation would balance under the following circumstances: where m = 1kg, v(1) = 5, v(2) = 1, v(3) = 3 and v(4) = 3. Or in other words: ...

    Even in an elastic collision, selecting arbitrary values for the velocities chosen so that momentum is conserved won't guarantee that kinetic energy is conserved. If you imagine a situation in which two balls collide, one of which is initially moving with a speed V and the other is stationary, then if as a result of the collision the one that was moving is brought to rest and the one that was at rest moves off with speed v, then both kinetic energy and momentum would be conserved and the collision would be elastic.
    My reply doesn't just apply to Old Fool but also DrRocket and CSMYTH3025 as well............You lot are just pettifogging!!!

    For the sake of the argument you ALWAYS assume a perfect elastic collision in the case of conservation of energy for metal balls colliding. Any heat loss would be comparatively small.

    I mean look at Newton's Cradle. How much loss do you get for sound and heat there. And any losses WOULD apply to meomentum as well because the balls very gradually slow down.



    Come on now..........are you serious?!!
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    Quote Originally Posted by galexander
    My reply doesn't just apply to Old Fool but also DrRocket and CSMYTH3025 as well............You lot are just pettifogging!!!

    For the sake of the argument you ALWAYS assume a perfect elastic collision in the case of conservation of energy for metal balls colliding. Any heat loss would be comparatively small.

    I mean look at Newton's Cradle. How much loss do you get for sound and heat there. And any losses WOULD apply to meomentum as well because the balls very gradually slow down.



    Come on now..........are you serious?!!
    Those lot are not pettifogging. They are serious, and correct. The heat loss is comparatively small, but you didn't start out with much energy to begin with. Here is a good exercise for you. Calculate the heat rise of the metal balls in the Newton's cradle if it absorbs the initial kinetic energy of the steel ball. Do you think you would be able to measure it?

    As far as the conservation of momentum in Newtons cradle is concerned, the problem is complicated by the connection of the balls to the wires of the cradle.
    When you first release the ball, it has no momentum. It gains momentum by interaction with the cradle through tension in the strings. Essentially you are transferring momentum to the ball from the cradle, the table it is resting on, and ultimately the earth. But, the mass of these is so large, comparatively, that you cannot see any movement. But, ultimately, you started with zero momentum when the ball was released, and you ended with zero when it came to rest.
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    Quote Originally Posted by Harold14370
    Quote Originally Posted by galexander
    My reply doesn't just apply to Old Fool but also DrRocket and CSMYTH3025 as well............You lot are just pettifogging!!!

    For the sake of the argument you ALWAYS assume a perfect elastic collision in the case of conservation of energy for metal balls colliding. Any heat loss would be comparatively small.

    I mean look at Newton's Cradle. How much loss do you get for sound and heat there. And any losses WOULD apply to meomentum as well because the balls very gradually slow down.



    Come on now..........are you serious?!!
    Those lot are not pettifogging. They are serious, and correct. The heat loss is comparatively small, but you didn't start out with much energy to begin with. Here is a good exercise for you. Calculate the heat rise of the metal balls in the Newton's cradle if it absorbs the initial kinetic energy of the steel ball. Do you think you would be able to measure it?

    As far as the conservation of momentum in Newtons cradle is concerned, the problem is complicated by the connection of the balls to the wires of the cradle.
    When you first release the ball, it has no momentum. It gains momentum by interaction with the cradle through tension in the strings. Essentially you are transferring momentum to the ball from the cradle, the table it is resting on, and ultimately the earth. But, the mass of these is so large, comparatively, that you cannot see any movement. But, ultimately, you started with zero momentum when the ball was released, and you ended with zero when it came to rest.
    Nonsense.

    If the kinetic energy is reduced then SO IS momentum.

    Kinetic energy is 1/2mv2 and since 'm' is static the velocity is reduced as the kinetic energy is reduced.

    But momentum is dependent on 'v' as well so it reduces as well...........!

    Can you not even follow the basics?!!
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    Quote Originally Posted by galexander

    My reply doesn't just apply to Old Fool but also DrRocket and CSMYTH3025 as well............You lot are just pettifogging!!!

    Come on now..........are you serious?!!
    I posted my reply in a hurry before I went to work last night. When I got home this morning I reviewed it and I must admit that there is a certain amount of (unintentional) pettifogging going on there. Not the sort of thing you're thinking of, though. I made transcribing errors and an analytical error in my reply as follows:

    "...1kg x 5 m/s ---> and <--- 1 kg x 3 m/s, producing a resultant momentum for the system of both metal balls equal to ---> 2 kg-m/s. Please note that momentum is a vector quantity (it has both magnitude and direction)..."


    I used the wrong velocity for the second ball (it should have been 1 m/s rather than 3 m/s). Thus, 5kg-(m/s) ---> velocity for the first ball and <--- 1 kg-(m/s) velocity for the second ball in the collision would produce a net momentum for the system of 4 kg(m/s)---> . The fact that the momentum of the system as a whole is not a fixed point is important when calculating the kinetic energy of the system. (I will explain this later)

    Also, because of the Wikipedia explanation regarding kinetic energy in a perfectly elastic collision which, in short, says "...Thus the bodies simply exchange velocities...", I should have pointed out that the "conserved" momentum you described as "...(1 x 5) + (1 x 1) = (1 x 3) + (1 x 3)..." is incorrect and would have been (5 kg-m/s--->) + (<---1 kg-m/s) = (<---1 kg-m/s) + (5 kg-m/s--->). Again, these velocities are vector quantities and have both magnitude and direction.

    Later in my post I calculated the kinetic energy of these balls = 13 Joules. Unfortunately, I overlooked an important feature of this particular type of collision which was also described in the Wikipedia article on Kinetic Energy, as follows:

    "...The kinetic energy of ... systems (such as our experiment) depends on the choice of reference frame: the reference frame that gives the minimum value of that energy is the center of momentum frame, i.e. the reference frame in which the total momentum of the system is zero..."

    In our experiment there is a moving central point between the balls at which their net momentum (approaching or receding) is zero. Since the masses are equal, the "positive and "negative" velocities must also be equal and, in fact, are 3m/s for each ball relative to this center of momentum.

    With this in mind, the kinetic energy for each of the two parts of this system would be (1/2)(kg)(3m/s) = 4.5 kg(m/s) = 4.5 Joules, or 9 Joules total.

    As always, I might be misunderstanding this whole thing. Feel free to correct any conceptual or arithmetic errors I may have made.

    Chris
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    I think that there is a simple resolution to this apparent puzzle. If one restricts the discussion to elastic collisions, it still isn't permissible to pluck numbers out of the sky so that they satisfy the momentum equation and then expect them to also satisfy the kinetic energy equation, as was done in the original post.

    If we have two independent equations, say,

    F(w,x,y,z) = 0 and G(w,x,y,z) = 0, you can't simply select values of w,x,y and z which satisfy the first and expect them to satisfy the second also. But this is exactly what was done in the example given in the original post. The two equations have to be solved together, not independently. If it was the case that all solutions of the first were also solutions of the second, the two equations wouldn't be independent.

    An equation such as v(1) + v(2) = v(3) + v(4) can be solved by an infinite variety of sets of values for v(1), v(2), v(3) and v(4). However, not all of these sets of values will also solve the kinetic energy equation - there is no reason why they should do.

    This is not just the case for problems involving momentum and energy, it is true of any problem involving the solution of more than one independent equation (or any problem involving simultaneous equations).
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  11. #10  
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    Quote Originally Posted by galexander
    Nonsense.

    If the kinetic energy is reduced then SO IS momentum.

    Kinetic energy is 1/2mv2 and since 'm' is static the velocity is reduced as the kinetic energy is reduced.

    But momentum is dependent on 'v' as well so it reduces as well...........!

    Can you not even follow the basics?!!
    Wrong

    Consider two masses of 1 kg each. One at rest, the second moving at 2 m/s, say to the left. Consider a perfectly in elastic collision. Let's assume it occurs in a vacuum so that there is no sound to consider.

    Before the collision:

    P: =

    KE : =


    After the collision one body of 2 kg moving at 1 m/s to the left so as to conserve momentum.

    P: =

    KE: =

    Momentum is conserved, but kinetic energy is lost to heat.

    Can you not understand even the basics ?
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    Still not convinced by any of you I'm afraid.

    I'm sure if you experimentally measured heat loss it still wouldn't account for the calculated differences between kinetic energy and momentum.

    You're clutching at straws surely?

    None of you has come up as yet with a clear and simple answer to the problem. You're just trying to cover things over with detail.
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    Quote Originally Posted by galexander
    Still not convinced by any of you I'm afraid.

    I'm sure if you experimentally measured heat loss it still wouldn't account for the calculated differences between kinetic energy and momentum.

    You're clutching at straws surely?

    None of you has come up as yet with a clear and simple answer to the problem. You're just trying to cover things over with detail.
    wrong

    The difficulty lies with your lack of comprehension.

    The explanation has been provided. This is rather simple freshman physics. It is correct. Understanding it is your bproblem.
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    Quote Originally Posted by galexander
    ...I'm sure if you experimentally measured heat loss it still wouldn't account for the calculated differences between kinetic energy and momentum....

    ...None of you has come up as yet with a clear and simple answer to the problem. You're just trying to cover things over with detail.
    In an ideal elastic collision (billiard balls and air hockey pucks being two approximate examples) the momentum and kinetic energy of the parts before and after the collision are conserved.

    To avoid repeating myself, the Wikipedia articles on Momentum (here: http://en.wikipedia.org/wiki/Momentum ) and Kinetic Energy
    (here: http://en.wikipedia.org/wiki/Kinetic_energy ) provide the reader with a great amount of detail about these relationships. This detail is offered for the purpose of explaining these phenomena - not for the purpose of covering up your imagined unexplainable cosmic mystery.

    If you want a clear and simple answer, then



    , and


    both before and after the collision. As I stated earlier, make sure you choose the center of momentum for this system when making these calculations.

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    galexander,

    One mistake you seem to be making is in thinking that momentum is a scalar quantity. It's not. It's a vector.

    Think about what happens when you bounce a ball off the wall and it rebounds with equal and opposite velocity. The ball does not have the same momentum it started with. It started with positive momentum and after the collision has negative momentum. So how is momentum conserved? The momentum was transferred to the wall. Chew on that for a while.
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    Quote Originally Posted by Harold14370
    galexander,

    One mistake you seem to be making is in thinking that momentum is a scalar quantity. It's not. It's a vector.

    Think about what happens when you bounce a ball off the wall and it rebounds with equal and opposite velocity. The ball does not have the same momentum it started with. It started with positive momentum and after the collision has negative momentum. So how is momentum conserved? The momentum was transferred to the wall. Chew on that for a while.
    Well since Kinetic Energy is based upon velocity and velocity is always a vector, cannot Kinetic Energy also be considered a vector quantity?

    When your ball is bounced off the wall, all the Kinetic Energy is also absorbed by the wall just as the Momentum is.

    Have a think about that for a while!
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    Quote Originally Posted by galexander
    Well since Kinetic Energy is based upon velocity and velocity is always a vector, cannot Kinetic Energy also be considered a vector quantity?

    When your ball is bounced off the wall, all the Kinetic Energy is also absorbed by the wall just as the Momentum is.

    Have a think about that for a while!
    No

    It is now more than evident that you did not pose your question in good faith and don't care about an answer in terms of basic physics.

    Troll. Please go straight to hell.
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    DIPLOMACY The best diplomat is one who can tell someone to go to a place really warm such that they feel that they will even enjoy the trip.
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    Quote Originally Posted by questor
    DIPLOMACY The best diplomat is one who can tell someone to go to a place really warm such that they feel that they will even enjoy the trip.
    The unwarranted assumption being made is that I care whether or not he enjoys the trip.

    May the seas be rough, the wind cold, the food rotten. May pestilence prevail and body parts decay and fall off.

    And I hope his Super Bowl seats were condemned by the Fire Marshal.
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    And that his plans for the week were delayed by the the big storm?

    And that he had to pay a lot for the overpriced hookers?

    Yes, we're no dips, but lips.

    And that his team lost?
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    Quote Originally Posted by DrRocket
    The unwarranted assumption being made is that I care whether or not he enjoys the trip.

    May the seas be rough, the wind cold, the food rotten. May pestilence prevail and body parts decay and fall off.

    And I hope his Super Bowl seats were condemned by the Fire Marshal.
    And upon reaching the infernal Stygian abyss may galexander have sand pounded up his ass by Beelzebub himself. Unless, of course, galexander enjoys that sort of thing, then may he be denied the pleasure!
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    Quote Originally Posted by galexander
    Quote Originally Posted by Harold14370
    galexander,

    One mistake you seem to be making is in thinking that momentum is a scalar quantity. It's not. It's a vector.

    Think about what happens when you bounce a ball off the wall and it rebounds with equal and opposite velocity. The ball does not have the same momentum it started with. It started with positive momentum and after the collision has negative momentum. So how is momentum conserved? The momentum was transferred to the wall. Chew on that for a while.
    Well since Kinetic Energy is based upon velocity and velocity is always a vector, cannot Kinetic Energy also be considered a vector quantity?

    When your ball is bounced off the wall, all the Kinetic Energy is also absorbed by the wall just as the Momentum is.

    Have a think about that for a while!
    I was preparing a reply explaining why "...all the kinetic energy is also absorbed by the wall just as momentum is..." is an incorrect statement (replete with mathematical details) when I noticed the posts that have come in on this thread.

    The consensus here seems to be that I would be wasting my time, so I'll just say that the statement is wrong and let it go at that.

    It hasn't been a complete loss, though. I got a lot of practice using the TeX feature - which is new to me. It's a very useful tool.

    Chris
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    Quote Originally Posted by CSMYTH3025
    Quote Originally Posted by galexander
    Quote Originally Posted by Harold14370
    galexander,

    One mistake you seem to be making is in thinking that momentum is a scalar quantity. It's not. It's a vector.

    Think about what happens when you bounce a ball off the wall and it rebounds with equal and opposite velocity. The ball does not have the same momentum it started with. It started with positive momentum and after the collision has negative momentum. So how is momentum conserved? The momentum was transferred to the wall. Chew on that for a while.
    Well since Kinetic Energy is based upon velocity and velocity is always a vector, cannot Kinetic Energy also be considered a vector quantity?

    When your ball is bounced off the wall, all the Kinetic Energy is also absorbed by the wall just as the Momentum is.

    Have a think about that for a while!
    I was preparing a reply explaining why "...all the kinetic energy is also absorbed by the wall just as momentum is..." is an incorrect statement (replete with mathematical details) when I noticed the posts that have come in on this thread.

    The consensus here seems to be that I would be wasting my time, so I'll just say that the statement is wrong and let it go at that.

    It hasn't been a complete loss, though. I got a lot of practice using the TeX feature - which is new to me. It's a very useful tool.

    Chris
    Yes, but just in case anybody else may be interested in why g is wrong: the energy is proportional to the square of the velocity, and the square of a negative number is positive. So the ball still has the same KE after it bounces off the wall. It did not give up any to the wall.
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    Quote Originally Posted by Harold14370
    Quote Originally Posted by CSMYTH3025
    Quote Originally Posted by galexander
    Quote Originally Posted by Harold14370
    galexander,

    One mistake you seem to be making is in thinking that momentum is a scalar quantity. It's not. It's a vector.

    Think about what happens when you bounce a ball off the wall and it rebounds with equal and opposite velocity. The ball does not have the same momentum it started with. It started with positive momentum and after the collision has negative momentum. So how is momentum conserved? The momentum was transferred to the wall. Chew on that for a while.
    Well since Kinetic Energy is based upon velocity and velocity is always a vector, cannot Kinetic Energy also be considered a vector quantity?

    When your ball is bounced off the wall, all the Kinetic Energy is also absorbed by the wall just as the Momentum is.

    Have a think about that for a while!
    I was preparing a reply explaining why "...all the kinetic energy is also absorbed by the wall just as momentum is..." is an incorrect statement (replete with mathematical details) when I noticed the posts that have come in on this thread.

    The consensus here seems to be that I would be wasting my time, so I'll just say that the statement is wrong and let it go at that.

    It hasn't been a complete loss, though. I got a lot of practice using the TeX feature - which is new to me. It's a very useful tool.

    Chris
    Yes, but just in case anybody else may be interested in why g is wrong: the energy is proportional to the square of the velocity, and the square of a negative number is positive. So the ball still has the same KE after it bounces off the wall. It did not give up any to the wall.
    Interesting observation Harold14370.

    However there must be some vector associated with Kinetic Energy as at a right angle to the speeding ball the Kinetic Energy has a value of zero and cannot be transferred. The impact, i.e. with a wall or another ball, has to be square on.
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    If a is a vector going from left to right, then a vector of the same size but going from right to left, is -a. However, kinetic energy is never negative. Kinetic energy isn't a vector. The vectors associated with the direction in which a body is moving are its velocity and momentum.
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    Quote Originally Posted by galexander
    Quote Originally Posted by Harold14370
    Yes, but just in case anybody else may be interested in why g is wrong: the energy is proportional to the square of the velocity, and the square of a negative number is positive. So the ball still has the same KE after it bounces off the wall. It did not give up any to the wall.
    Interesting observation Harold14370.

    However there must be some vector associated with Kinetic Energy as at a right angle to the speeding ball the Kinetic Energy has a value of zero and cannot be transferred. The impact, i.e. with a wall or another ball, has to be square on.
    Wrong again troll. Completely, totally wrong.

    Kinetic energy is a scalar, period. There is no direction to it.

    An elastic collision can be oblique. There is nothing magic about a right angle collision except for the recoil angle. The vector quantity momentum is always conserved. If the collision is perfectly elastic then the scalar kinetic energy is also conserved.

    But you may well know this, and simply want to stir the pot and confuse neophytes. Troll indeed.
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    Quote Originally Posted by Old Fool
    If a is a vector going from left to right, then a vector of the same size but going from right to left, is -a. However, kinetic energy is never negative. Kinetic energy isn't a vector. The vectors associated with the direction in which a body is moving are its velocity and momentum.
    Correct

    Unfortunately galexander is not interested in the physics, but only in creating a stir.
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    Quote Originally Posted by galexander
    Quote Originally Posted by Harold14370
    ...Yes, but just in case anybody else may be interested in why g is wrong: the energy is proportional to the square of the velocity, and the square of a negative number is positive. So the ball still has the same KE after it bounces off the wall. It did not give up any to the wall.
    Interesting observation Harold14370.

    However there must be some vector associated with Kinetic Energy as at a right angle to the speeding ball the Kinetic Energy has a value of zero and cannot be transferred. The impact, i.e. with a wall or another ball, has to be square on.
    Harold14370 is right - momentum is a vector quantity. It has both magnitude and direction. Kinetic energy is just a quantity. It has magnitude, but no direction.

    Quoting from the Wikipedia article on momentum which I referenced in my previous post:

    "...If an object is moving in any reference frame, then it has momentum in that frame. It is important to note that momentum is frame dependent. That is, the same object may have a certain momentum in one frame of reference, but a different amount in another frame. For example, a moving object has momentum in a reference frame fixed to a spot on the ground, while at the same time having 0 momentum in a reference frame attached to the object's center of mass.

    The amount of momentum that an object has depends on two physical quantities: the mass and the velocity of the moving object in the frame of reference. In physics, the usual symbol for momentum is a bold p (bold because it is a vector); so this can be written



    where is the momentum, is the mass and V is the velocity..."
    Notice that is a vector quantity - it can be positive (moving --->) or negative (moving <---)

    Kinetic energy is just a quantity - it has magnitude, but no direction according to the following formula:




    In our case if the momentum of the ball before the bounce is (moving --->), then the kinetic energy is (a positive quantity of energy that has no direction associated with it).

    On the return bounce (assuming a perfectly elastic collision) the momentum of the ball would be (moving <---) and the kinetic energy would be (also a positive quantity of energy that has no direction associated with it).

    In this thought experiment there is, in fact, a miniscule amount of momentum transferred by the ball to the wall. Assuming the wall is attached the the Earth, the mass associated with the Earth-wall system is so large compared to the mass of the ball that the increase in momentum of the Earth-wall component in the positive (--->) direction is immeasurable. Likewise, there is a transfer of momentum from the wall to the ball in the negative direction (<---). Thus, whereas the ball-wall system began by initially converging on the center of momentum of the system before the collision, they diverge away from the center of momentum of the system after the collision.

    The kinetic energy of the ball-wall-Earth system remains unchanged throughout the experiment (provided the center of momentum of the ball-wall-Earth system is used for the measurement of the velocities). Also, the net momentum of the ball-wall-Earth system remains unchanged throughout the experiment (provided the center of momentum of the ball-wall-Earth system is the frame of reference used for the measurement of the velocities). This can be shown mathematically, but the calculation is more involved than the simple calculations shown above.

    All of the above applies to collisions at various angles (as DrRocket pointed out). The calaculations for collisions at an acute angle are also more involved than our simple example, but not terribly so.

    Chris
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    Quote Originally Posted by Old Fool
    If a is a vector going from left to right, then a vector of the same size but going from right to left, is -a. However, kinetic energy is never negative. Kinetic energy isn't a vector. The vectors associated with the direction in which a body is moving are its velocity and momentum.
    But there is a slight conundrum here.

    Velocity is a vector and it ALWAYS possesses Kinetic Energy.

    So why is it Kinetic Energy can't be a vector also?

    Since Kinetic Energy always has a direction to it, it must therefore be a vector.

    Q.E.D. :-D
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    Since Kinetic Energy always has a direction to it, it must therefore be a vector.


    Merely associating a direction with something doesn't make it a vector. A vector must obey the rules for vector addition and kinetic energy doesn't do this.
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    Quote Originally Posted by galexander

    Since Kinetic Energy always has a direction to it, it must therefore be a vector.

    Q.E.D. :-D
    The kinetic energy of the random motion of the molecules in a pot of boiling water is, when taken together, greater than the kinetic energy of the random motion of the molecules in a pot of cold water.

    You might be able to attribute a direction to the kinetic energy of a particular molecule at a particular moment in time relative to an arbitrary point in space, but how would you attribute a direction to the whole pot of molecules?

    I realize that this form of energy is called thermal energy. If taken to the appropriate scale, however, it reduces to as far as I know.

    A stationary pot of boiling water has kinetic energy attributed to its temperature. This kinetic energy due to temperature doesn't have a particular direction and it remains the same whether the pot is stationary or moving on a train.

    The pot of boiling water would also have a certain kinetic energy in the frame of reference of someone standing next to the train tracks due to its mass and relative velocity. This same pot of boiling water would have no kinetic energy due to its velocity relative to the stove on the train on which it's sitting.

    As you can see: Kinetic energy does not always have a direction to it, it must not therefore be a vector.

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    Quote Originally Posted by CSMYTH3025
    Quote Originally Posted by galexander

    Since Kinetic Energy always has a direction to it, it must therefore be a vector.

    Q.E.D. :-D
    A stationary pot of boiling water has kinetic energy attributed to its temperature. This kinetic energy due to temperature doesn't have a particular direction and it remains the same whether the pot is stationary or moving on a train.

    The pot of boiling water would also have a certain kinetic energy in the frame of reference of someone standing next to the train tracks due to its mass and relative velocity. This same pot of boiling water would have no kinetic energy due to its velocity relative to the stove on the train on which it's sitting.

    As you can see: Kinetic energy does not always have a direction to it, it must not therefore be a vector.


    is a scalar. Hence so is

    It is that simple.

    You will not convince galexander. He is a troll. He is not interested in learning.
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    Quote Originally Posted by Old Fool

    Since Kinetic Energy always has a direction to it, it must therefore be a vector.


    Merely associating a direction with something doesn't make it a vector. A vector must obey the rules for vector addition and kinetic energy doesn't do this.
    Oh yes it does!

    Kinetic Energy does observe the laws of vector addition.

    Just look at impacting balls where angles of collision are involved.

    Looks very much like vector addition to me. :wink:
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    Quote Originally Posted by galexander
    Oh yes it does!

    Kinetic Energy does observe the laws of vector addition.

    Just look at impacting balls where angles of collision are involved.

    Looks very much like vector addition to me. :wink:
    You seem to be fixated on perfectly elastic collisions - which can be described in theory but just doesn't happen in the macroscopic world of human experience.

    The collisions we observe on a macroscopic scale are inelastic collisions. If you look at collisions ranging from car wrecks to the impact of Shoemaker-Levy 9 with Jupiter you see in every case that the the laws of vector addition are very obviously not observed. The mangled remains of cars and the enormous explosive scars in the atmosphere of Jupiter are visible evidence of this effect. To be sure, kinetic energy is conserved - but direction is definitely not conserved when viewing the aftermath of these collisions.

    On a smaller scale, even the collision of billiard balls can be shown to be slightly inelastic when measured with great precision.

    I suspect you already know this. Why do you continue to post replies that only serve to confuse the casual reader about matters that are easily explained?

    Wouldn't your time and talents be better used in discussing more interesting questions?

    Chris
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    Kinetic energy doesn't generally add in the way that vectors do no matter whether the collision is elastic or inelastic. Momentum adds as a vector and momentum depends linearly on velocity. However, kinetic energy depends on the square of the velocity. If the momenta form the sides of a vector addition triangle then the velocities squared won't form the sides of a similar triangle.
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    Quote Originally Posted by CSMYTH3025
    Why do you continue to post replies that only serve to confuse the casual reader about matters that are easily explained?

    Chris
    Because he is a damn troll !
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    Quote Originally Posted by DrRocket
    Quote Originally Posted by CSMYTH3025
    Why do you continue to post replies that only serve to confuse the casual reader about matters that are easily explained?

    Chris
    Because he is a damn troll !
    yeeeeeep! A troll is a troll, and he's just promoting stupidity. Best to ignore him at this point
    Wise men speak because they have something to say; Fools, because they have to say something.
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    Quote Originally Posted by CSMYTH3025
    Quote Originally Posted by galexander
    Oh yes it does!

    Kinetic Energy does observe the laws of vector addition.

    Just look at impacting balls where angles of collision are involved.

    Looks very much like vector addition to me. :wink:
    You seem to be fixated on perfectly elastic collisions - which can be described in theory but just doesn't happen in the macroscopic world of human experience.

    The collisions we observe on a macroscopic scale are inelastic collisions. If you look at collisions ranging from car wrecks to the impact of Shoemaker-Levy 9 with Jupiter you see in every case that the the laws of vector addition are very obviously not observed. The mangled remains of cars and the enormous explosive scars in the atmosphere of Jupiter are visible evidence of this effect. To be sure, kinetic energy is conserved - but direction is definitely not conserved when viewing the aftermath of these collisions.

    On a smaller scale, even the collision of billiard balls can be shown to be slightly inelastic when measured with great precision.

    I suspect you already know this. Why do you continue to post replies that only serve to confuse the casual reader about matters that are easily explained?

    Wouldn't your time and talents be better used in discussing more interesting questions?

    Chris
    Pettifogging again.

    On the question, "Is kinetic energy a scalar or vector quantity?", Answers.com had the following to say:

    "Scalar. There is no direction associated with it."

    However as I have stated quite clearly previously Kinetic Energy ALWAYS has a direction associated to it.

    Give me one instance where it isn't.

    So what was Answers.com saying? *
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    Quote Originally Posted by galexander

    ....However as I have stated quite clearly previously Kinetic Energy ALWAYS has a direction associated to it.

    Give me one instance where it isn't.

    This is getting a bit old. Because of the quadratic nature of the formula by which it's calculated, kinetic energy NEVER has a direction associated with it. I believe you already know this.

    If two balls are approaching each other at 4 m/s relative to their common center of momentum, the first ball will have a momentum of (moving --->), and a kinetic energy of . The second ball will have a momentum of (moving <---) and a kinetic energy of .

    What direction do you ascribe to the 48 joules of kinetic energy of this system?

    This thread has become pointless, so I won't be posting any more replies to it.

    Chris
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    Quote Originally Posted by CSMYTH3025
    Quote Originally Posted by galexander

    ....However as I have stated quite clearly previously Kinetic Energy ALWAYS has a direction associated to it.

    Give me one instance where it isn't.

    This is getting a bit old. Because of the quadratic nature of the formula by which it's calculated, kinetic energy NEVER has a direction associated with it. I believe you already know this.

    If two balls are approaching each other at 4 m/s relative to their common center of momentum, the first ball will have a momentum of (moving --->), and a kinetic energy of . The second ball will have a momentum of (moving <---) and a kinetic energy of .

    What direction do you ascribe to the 48 joules of kinetic energy of this system?

    This thread has become pointless, so I won't be posting any more replies to it.

    Chris
    Forget about quadratics.

    A speeding ball with Kinetic Energy ALWAYS has direction to it.

    End of story.

    I don't know why you keep failing to see the obvious?

    :x :x :x :x :x :x :x :x :x
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    Actually, if a person ignores galexander, there is quite a bit of useful information in this thread. Thanks everyone.
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    Lucky me. Lucky mud.
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    A speeding ball with Kinetic Energy ALWAYS has direction to it.
    A direction for V^2 would mean that it would be preserved nomatter the distance. If you give a billartball a kinetic energy by the time it reaches the other side of the earth it,s direction would have changed 180 degrees if it keeps it velocity and height constant.

    The impulse from a cue M*V is linear straight and therefor regarded as vectorial (linear with direction).

    If an impulse from a cue is strong enough a ball could theoretical come loose from a perfectly horizontal billarttable or loose some weight to it. Because the impuls from the cue is linear but the billart surface - horizontal everywhere - is rounded.
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    Quote Originally Posted by galexander
    Quote Originally Posted by CSMYTH3025
    Quote Originally Posted by galexander

    ....However as I have stated quite clearly previously Kinetic Energy ALWAYS has a direction associated to it.

    Give me one instance where it isn't.

    This is getting a bit old. Because of the quadratic nature of the formula by which it's calculated, kinetic energy NEVER has a direction associated with it. I believe you already know this.

    If two balls are approaching each other at 4 m/s relative to their common center of momentum, the first ball will have a momentum of (moving --->), and a kinetic energy of . The second ball will have a momentum of (moving <---) and a kinetic energy of .

    What direction do you ascribe to the 48 joules of kinetic energy of this system?

    This thread has become pointless, so I won't be posting any more replies to it.

    Chris
    Forget about quadratics.

    A speeding ball with Kinetic Energy ALWAYS has direction to it.

    End of story.

    I don't know why you keep failing to see the obvious?

    :x :x :x :x :x :x :x :x :x
    Ooooookay.... Yes, a moving ball has direction, which is also referred to as velocity. Momentum also has direction, and is a vector quantity.

    Energy, does not have direction. A spinning top has kinetic energy, quite a bit actually. But, which direction is the center of gravity moving in galexander?
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    I suppose Galexander does not regard a spinning objekt (like a billart ball with spin but not moving on the table) as having kinetic energy. In his view (I suppose) it is obvious that the kinetic energy of the parts to any marked point (on the billart or the floor) is zero just as the linear momentum is zero.

    P=MV to a marked spot on the table is zero but M is not zero. So V for the ball is zero.

    Isn,t it a bit strange to not consier V=0 when it comes to the kinetic energy then ? That means using two different values for V for both momentum and energy.

    In this case I would prefer to use the word "spinenergy" or other word too distinct from kinetic energy. Spinenergy has no direktion and in case of a billartball (without a mark on it) is even invisible because there is no solid axis.
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    Quote Originally Posted by Ghrasp
    I suppose Galexander does not regard a spinning objekt (like a billart ball with spin but not moving on the table) as having kinetic energy. In his view (I suppose) it is obvious that the kinetic energy of the parts to any marked point (on the billart or the floor) is zero just as the linear momentum is zero.

    P=MV to a marked spot on the table is zero but M is not zero. So V for the ball is zero.

    Isn,t it a bit strange to not consier V=0 when it comes to the kinetic energy then ? That means using two different values for V for both momentum and energy.

    In this case I would prefer to use the word "spinenergy" or other word too distinct from kinetic energy. Spinenergy has no direktion and in case of a billartball (without a mark on it) is even invisible because there is no solid axis.


    http://hyperphysics.phy-astr.gsu.edu/hbase/rke.html
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    Quote Originally Posted by Arcane_Mathematician
    Quote Originally Posted by galexander
    Quote Originally Posted by CSMYTH3025
    Quote Originally Posted by galexander

    ....However as I have stated quite clearly previously Kinetic Energy ALWAYS has a direction associated to it.

    Give me one instance where it isn't.

    This is getting a bit old. Because of the quadratic nature of the formula by which it's calculated, kinetic energy NEVER has a direction associated with it. I believe you already know this.

    If two balls are approaching each other at 4 m/s relative to their common center of momentum, the first ball will have a momentum of (moving --->), and a kinetic energy of . The second ball will have a momentum of (moving <---) and a kinetic energy of .

    What direction do you ascribe to the 48 joules of kinetic energy of this system?

    This thread has become pointless, so I won't be posting any more replies to it.

    Chris
    Forget about quadratics.

    A speeding ball with Kinetic Energy ALWAYS has direction to it.

    End of story.

    I don't know why you keep failing to see the obvious?

    :x :x :x :x :x :x :x :x :x
    Ooooookay.... Yes, a moving ball has direction, which is also referred to as velocity. Momentum also has direction, and is a vector quantity.

    Energy, does not have direction. A spinning top has kinetic energy, quite a bit actually. But, which direction is the center of gravity moving in galexander?
    But surely a spinning top has momentum as well since it has both mass and angular velocity?

    You appear to have forgotten this. And angular momentum is a VECTOR QUANTITY.

    Your example of a spinning top serves no useful purpose other than to serve as futile attempt at a red herring.

    And Ghrasp, it would appear you have fallen down the same hole.
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    No matter what reply anyone post's, the damned troll will just continue to howl LA, LA, LA, with his fingers jammed in his ear's. Just ignore him.
    I was some of the mud that got to sit up and look around.
    Lucky me. Lucky mud.
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    KE=1/2 I W^2 ?

    Been there, learned that allready aso with good grades also (so don,t try to be educative when no one is asking) Now I just happen to disagree with what I learned or at least question the texbooks on this.

    What you really mean to say is : 1/2 I W^2 = Ke just as well as MV^2 = Ke.
    In other words it,s an interpretation. So why not make distintion between 1/2 mV^2 and 1/2 mW^2 instead of throwing it on one pile of Ek ? That,s a question not a say-so.

    To me it makes a real difference when something stays at constant distance to something else or not.

    In case of a billart when a ball is on the billart rotating it stays at constant distance to all the other balls and the billart/ floor etc. thus it doesn,t move thus it has no kinetic energy in the linear sense. That,s basic difference from a ball moving on the billart. Fysics should express such basic differences in my opinion not throw it on one pile : KE.
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    Quote Originally Posted by Ghrasp
    KE=1/2 I W^2 ?

    Been there, learned that allready aso with good grades also (so don,t try to be educative when no one is asking) Now I just happen to disagree with what I learned or at least question the texbooks on this.

    What you really mean to say is : 1/2 I W^2 = Ke just as well as MV^2 = Ke.
    In other words it,s an interpretation. So why not make distintion between 1/2 mV^2 and 1/2 mW^2 instead of throwing it on one pile of Ek ? That,s a question not a say-so.

    To me it makes a real difference when something stays at constant distance to something else or not.

    In case of a billart when a ball is on the billart rotating it stays at constant distance to all the other balls and the billart/ floor etc. thus it doesn,t move thus it has no kinetic energy in the linear sense. That,s basic difference from a ball moving on the billart. Fysics should express such basic differences in my opinion not throw it on one pile : KE.
    Rotational KE like that applies to a body in rotation. Parts of the body are actually translating in a circulat orbit about an axis, and that motion is the source of the kinetic energy. As usual, you don't know what you are talking about.
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    Quote Originally Posted by Ghrasp
    KE=1/2 I W^2 ?

    Been there, learned that allready aso with good grades also (so don,t try to be educative when no one is asking) Now I just happen to disagree with what I learned or at least question the texbooks on this.

    What you really mean to say is : 1/2 I W^2 = Ke just as well as MV^2 = Ke.
    In other words it,s an interpretation. So why not make distintion between 1/2 mV^2 and 1/2 mW^2 instead of throwing it on one pile of Ek ? That,s a question not a say-so.

    To me it makes a real difference when something stays at constant distance to something else or not.

    In case of a billart when a ball is on the billart rotating it stays at constant distance to all the other balls and the billart/ floor etc. thus it doesn,t move thus it has no kinetic energy in the linear sense. That,s basic difference from a ball moving on the billart. Fysics should express such basic differences in my opinion not throw it on one pile : KE.
    Thank you Ghrasp.

    At last I seem to be getting through to someone.

    At least you now admit that "some" of the classical physics could be wrong.

    Now I just happen to disagree with what I learned or at least question the texbooks on this.
    Anyone else...................... :P
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    Quote Originally Posted by galexander
    Quote Originally Posted by Arcane_Mathematician
    Quote Originally Posted by galexander
    Quote Originally Posted by CSMYTH3025
    Quote Originally Posted by galexander

    ....However as I have stated quite clearly previously Kinetic Energy ALWAYS has a direction associated to it.

    Give me one instance where it isn't.

    This is getting a bit old. Because of the quadratic nature of the formula by which it's calculated, kinetic energy NEVER has a direction associated with it. I believe you already know this.

    If two balls are approaching each other at 4 m/s relative to their common center of momentum, the first ball will have a momentum of (moving --->), and a kinetic energy of . The second ball will have a momentum of (moving <---) and a kinetic energy of .

    What direction do you ascribe to the 48 joules of kinetic energy of this system?

    This thread has become pointless, so I won't be posting any more replies to it.

    Chris
    Forget about quadratics.

    A speeding ball with Kinetic Energy ALWAYS has direction to it.

    End of story.

    I don't know why you keep failing to see the obvious?

    :x :x :x :x :x :x :x :x :x
    Ooooookay.... Yes, a moving ball has direction, which is also referred to as velocity. Momentum also has direction, and is a vector quantity.

    Energy, does not have direction. A spinning top has kinetic energy, quite a bit actually. But, which direction is the center of gravity moving in galexander?
    But surely a spinning top has momentum as well since it has both mass and angular velocity?

    You appear to have forgotten this. And angular momentum is a VECTOR QUANTITY.

    Your example of a spinning top serves no useful purpose other than to serve as futile attempt at a red herring.

    And Ghrasp, it would appear you have fallen down the same hole.
    yes, there is angular momentum. what direction is that vector pointed? and now, tell me, what direction is the kinetic energy's direction pointed in?
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    Quote Originally Posted by galexander
    Thank you Ghrasp.

    At last I seem to be getting through to someone.

    At least you now admit that "some" of the classical physics could be wrong.

    Quote:
    Now I just happen to disagree with what I learned or at least question the texbooks on this.


    Anyone else......................
    Ah yes, Ghrasp is a paragon of lucidity;http://www.thescienceforum.com/searc..._author=Ghrasp.
    I was some of the mud that got to sit up and look around.
    Lucky me. Lucky mud.
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    Quote Originally Posted by GiantEvil
    Quote Originally Posted by galexander
    Thank you Ghrasp.

    At last I seem to be getting through to someone.

    At least you now admit that "some" of the classical physics could be wrong.

    Quote:
    Now I just happen to disagree with what I learned or at least question the texbooks on this.


    Anyone else......................
    Ah yes, Ghrasp is a paragon of lucidity;http://www.thescienceforum.com/searc..._author=Ghrasp.

    lucidity = stupidity ????
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    lucidity = stupidity ????
    Think blinding light, a concentration of brain frying electromagnetic radiation extending to the gamma. I.e; blind drunk in Texas.
    I was some of the mud that got to sit up and look around.
    Lucky me. Lucky mud.
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    Be welcome .

    KE does not come from anything you derive it from calculation ; 1/2 mV 2 and/ór 1/2 IW^2. It says nothing about a energy source or something. It,s looking at a given moment towards a billard where you see different balls in different motional situation to each other and the billardtable/floor.....

    On a billard two balls can have same kinetic energy while both have different speed. The distinction is in the calculation but not in the result when the two are added.

    What,s against distinction ? it,s mostly where intelligence starts.

    A spinning ball lying in rest on a billart to me has no kinetic energy but spinenergy.
    If it,s a combined situation of a ball with a motion and spinning the total energy would be Ek+Es.

    The advantage is that this way kinetic energy has a directional component but the total energy has not (because only the total energy (of motion) is not telling anything about a V for the ball, it could be a ball with no V and only spin....thus no direktion. Aplying a vectoris impossible then.

    Where I read "E kin"= x I have no idea if there is spin or not or how much. Thus no idea about V (linear) either.

    Not making that distinction Galexander's idea is idiotic but making it as he does and asks for it makes sense.

    It,s big part about the use of word and terms and attachement to them.

    If it pleases someone I could (but why would I) use the word kinetic energy instead of motional energy and then "spinenergy" (Es) related to spin and speedenergy (Ev) or vectorial energy (Ev) related to vectorial energy. As spin is not vectorial same way as speed.

    Then kinetic energy is no longer vectorial (suppose even Galexander would agree) but it still has a vectorial component because Ek=Es+Ev and Ev is vectorial component.
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    Quote Originally Posted by GiantEvil
    Quote Originally Posted by galexander
    Thank you Ghrasp.

    At last I seem to be getting through to someone.

    At least you now admit that "some" of the classical physics could be wrong.

    Quote:
    Now I just happen to disagree with what I learned or at least question the texbooks on this.


    Anyone else......................
    Ah yes, Ghrasp is a paragon of lucidity;http://www.thescienceforum.com/searc..._author=Ghrasp.
    You physics buffs seem so open minded when it comes to mass not really existing and just being a form of energy, physicists "psychically" interacting with sub-atomic particles and particles that go backwards in time........etc,etc.

    But when it comes to questioning Newton's divine formulae, apparently it's an absolute no, no.

    However there may be an answer to this as well.

    There are some brilliantly revealing choice quotes from Niels Bohr which gave the game away that it was just a team effort to keep the ball rolling and to pull off a publicity stunt that would go down in history.

    And it looks like they did it folks........!

    And I also note my thread now appears to be on the way to Pseudoscience.

    Well what a surprise............! :wink:
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    Quote Originally Posted by galexander
    Quote Originally Posted by GiantEvil
    Quote Originally Posted by galexander
    Thank you Ghrasp.

    At last I seem to be getting through to someone.

    At least you now admit that "some" of the classical physics could be wrong.

    Quote:
    Now I just happen to disagree with what I learned or at least question the texbooks on this.


    Anyone else......................
    Ah yes, Ghrasp is a paragon of lucidity;http://www.thescienceforum.com/searc..._author=Ghrasp.
    You physics buffs seem so open minded when it comes to mass not really existing and just being a form of energy, physicists "psychically" interacting with sub-atomic particles and particles that go backwards in time........etc,etc.

    But when it comes to questioning Newton's divine formulae, apparently it's an absolute no, no.

    However there may be an answer to this as well.

    There are some brilliantly revealing choice quotes from Niels Bohr which gave the game away that it was just a team effort to keep the ball rolling and to pull off a publicity stunt that would go down in history.

    And it looks like they did it folks........!

    And I also note my thread now appears to be on the way to Pseudoscience.

    Well what a surprise............! :wink:
    It's because you are a quack. You are a bane to education.
    Wise men speak because they have something to say; Fools, because they have to say something.
    -Plato

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    However there may be an answer to this as well.

    Studying fysics it is thought from the first ay at school that nature, thus fysics can,t be approached by intuition :
    "you,re intuition lies to you don,t trust it (yourself) leave it outside" it,s written like this above the door to study fysics.

    Reality is tought to be counterintuitive thus intuition is implicitly tought to be irrealistic. Once that is learned and accepted almost anything becomes acceptible.

    Take the example of particles and anti-particles...
    Billiardballs often have a dot or some marking on them.. A ball spins on the table but does not change position (to the billiard).

    Every cycle/period the dot returns to the same position relative to any chosen point on the billart or any other point, line or frame of reference or any observer. So dx is clearly zero for 1,2,3, 4.... n revolutions.

    We can look for a certain rotational point in a cycle when the dot is turned to one side of the billard for example visible for someone.

    If f=1/sec, T= 1 sec. So for each second the dot returns to same position. So dx/dt =0/sec V=zero.

    For a fraction of T there is always an opposite fraction of the cycle, Opposite on the ball.
    Be it imaginary another dot or the same dot half a cycle later or earlier) For that opposite fraction of time ór opposite fraction of the ball at each moment the anti-dot always had opposite V then the mark, the real dot. If one sees the dot move left any anti dot moves right.
    V for dot and anti dot total therefor is always zero except if the eye and mind focusses on the dot (as a fragment) and not the ball as a whole. This is for all dots and anti-dots on the ball so it does not move on the billiard (as a two-dimensional euclid system) but moves "in itself" as a spinning ball and an energy with a pseudo-vectoriality.
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    Quote Originally Posted by Arcane_Mathematician
    Quote Originally Posted by galexander
    Quote Originally Posted by GiantEvil
    Quote Originally Posted by galexander
    Thank you Ghrasp.

    At last I seem to be getting through to someone.

    At least you now admit that "some" of the classical physics could be wrong.

    Quote:
    Now I just happen to disagree with what I learned or at least question the texbooks on this.


    Anyone else......................
    Ah yes, Ghrasp is a paragon of lucidity;http://www.thescienceforum.com/searc..._author=Ghrasp.
    You physics buffs seem so open minded when it comes to mass not really existing and just being a form of energy, physicists "psychically" interacting with sub-atomic particles and particles that go backwards in time........etc,etc.

    But when it comes to questioning Newton's divine formulae, apparently it's an absolute no, no.

    However there may be an answer to this as well.

    There are some brilliantly revealing choice quotes from Niels Bohr which gave the game away that it was just a team effort to keep the ball rolling and to pull off a publicity stunt that would go down in history.

    And it looks like they did it folks........!

    And I also note my thread now appears to be on the way to Pseudoscience.

    Well what a surprise............! :wink:
    It's because you are a quack. You are a bane to education.
    Well I would hold that quantum physicists are quacks.

    So was Newton to some extent though it is quite possible he wasn't wilfully in error.

    What the subject of physics obviously does not teach people is how to think for themselves.

    But too few people can these days. They think what they are taught or told to think.
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    Quote Originally Posted by galexander
    What the subject of physics obviously does not teach people is how to think for themselves.
    Why would it? We need critical thinking, logic and open-mindedness to pursue physics, but physics is not intended to teach these things. We need to be able to speak, write, eat food, drink water and breathe in order to research physics as well. Should it teach us these things as well?

    Quote Originally Posted by galexander
    But too few people can these days. They think what they are taught or told to think.
    The trouble with statements like this is that they're cheap and ubiquitous. Everyone who thinks they have a new idea accuses the establishment of narrow-mindedness. Millions of people make the claim every year, but only a minute fraction of those people are actually correct. What sets them apart from the rest is that they convince the establishment with good, reproducible evidence.

    If you're actually one of the few revolutionaries, you need to divert you energy from the clichéd rhetoric and devote yourself to presenting the evidence.
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    So was Newton to some extent though it is quite possible he wasn't wilfully in error.
    I really question if it,s Newton being in Error here. I think it,s really a discussion about interpreting and some boards that set certain rules for that.


    Ek= !/2 (MV^2 + IW^2) according to Newton's math. If Newton would consider Ek not being vectorial does that tell he considered the component 1/2 MV^2 not to be vectorial either ? Who says so ? Did Newton write that explicitly somewhere ?

    When one of these components is vectorial and one not (but pseudo or better (I think) cyclic) then they can,t be summed up as Ek being vectorial (in a linear way)
    But also not as "not vectorial". It,s just two different types of vectoriality.

    Vectorial or not vectorial it all becomes not defined or impossible to define without specification and distinction.

    Once it is specified like an objekt having no spin Ek=1,2 mV^2. The whole objekt moves one direction then instead of different parts different direktion and even opposite direktion. Then for Ek the vectoriality from speed and momentum continuous.

    The difficulty for some seems to be that if Ek is not definable as vectorial then that automatically defines it as "not vectorial".

    Not defined means that the Question "ïs Ek vectorial ?" is simply a wrong put question. Same as questions like "does god exist" ? Modern Filosophy has been quite clear on these things but unfortunately that,s not an integral part of physics studies.
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    Quote Originally Posted by galexander
    Quote Originally Posted by Arcane_Mathematician
    Quote Originally Posted by galexander
    Quote Originally Posted by GiantEvil
    Quote Originally Posted by galexander
    Thank you Ghrasp.

    At last I seem to be getting through to someone.

    At least you now admit that "some" of the classical physics could be wrong.

    Quote:
    Now I just happen to disagree with what I learned or at least question the texbooks on this.


    Anyone else......................
    Ah yes, Ghrasp is a paragon of lucidity;http://www.thescienceforum.com/searc..._author=Ghrasp.
    You physics buffs seem so open minded when it comes to mass not really existing and just being a form of energy, physicists "psychically" interacting with sub-atomic particles and particles that go backwards in time........etc,etc.

    But when it comes to questioning Newton's divine formulae, apparently it's an absolute no, no.

    However there may be an answer to this as well.

    There are some brilliantly revealing choice quotes from Niels Bohr which gave the game away that it was just a team effort to keep the ball rolling and to pull off a publicity stunt that would go down in history.

    And it looks like they did it folks........!

    And I also note my thread now appears to be on the way to Pseudoscience.

    Well what a surprise............! :wink:
    It's because you are a quack. You are a bane to education.
    Well I would hold that quantum physicists are quacks.

    So was Newton to some extent though it is quite possible he wasn't wilfully in error.

    What the subject of physics obviously does not teach people is how to think for themselves.

    But too few people can these days. They think what they are taught or told to think.
    Just to back up what I said about Quantum Physics I intend to post a fresh thread outlining an obvious problem with the theory in addition to the one I have already posted on the subject.

    When I get around to it, it concerns electrons accelerating in a cathode ray tube.
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    Quote Originally Posted by galexander

    Just to back up what I said about Quantum Physics I intend to post a fresh thread outlining an obvious problem with the theory in addition to the one I have already posted on the subject.

    When I get around to it, it concerns electrons accelerating in a cathode ray tube.
    I strongly suggest you take, and pass, an introductory physics course before posting any more threads outlining supposed problems. You are only embarrassing yourself.
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    He needs to be banned... Seriously.
    Wise men speak because they have something to say; Fools, because they have to say something.
    -Plato

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    Quote Originally Posted by Harold14370
    Quote Originally Posted by galexander

    Just to back up what I said about Quantum Physics I intend to post a fresh thread outlining an obvious problem with the theory in addition to the one I have already posted on the subject.

    When I get around to it, it concerns electrons accelerating in a cathode ray tube.
    I strongly suggest you take, and pass, an introductory physics course before posting any more threads outlining supposed problems. You are only embarrassing yourself.
    bold added

    Therein lies the rub.
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    Quote Originally Posted by Harold14370
    Quote Originally Posted by galexander

    Just to back up what I said about Quantum Physics I intend to post a fresh thread outlining an obvious problem with the theory in addition to the one I have already posted on the subject.

    When I get around to it, it concerns electrons accelerating in a cathode ray tube.
    I strongly suggest you take, and pass, an introductory physics course before posting any more threads outlining supposed problems. You are only embarrassing yourself.
    No, I insist.

    Further attempts at brainwashing by the orthodox powers that be will have no effect whatsoever. :x
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    Quote Originally Posted by Arcane_Mathematician
    He needs to be banned... Seriously.
    Presumably Arcane_Mathematician you support all forms of media censorship when it comes to anyone with the audacity to express views which contradict the orthodox.

    I suppose countries like Iran must represent an ideal for the likes of yourself. :x
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    Quote Originally Posted by galexander
    Quote Originally Posted by Harold14370
    Quote Originally Posted by galexander

    Just to back up what I said about Quantum Physics I intend to post a fresh thread outlining an obvious problem with the theory in addition to the one I have already posted on the subject.

    When I get around to it, it concerns electrons accelerating in a cathode ray tube.
    I strongly suggest you take, and pass, an introductory physics course before posting any more threads outlining supposed problems. You are only embarrassing yourself.
    No, I insist.

    Further attempts at brainwashing by the orthodox powers that be will have no effect whatsoever. :x
    Brainwashing... aka 'convincing'. Are you trying to brainwash us? Do you believe you're capable of doing so? If not, then why would you assume a conventional course in physics could do so? I think what you're afraid of is not brainwashing, but discovering that you are incorrect.

    I'll give you a spoiler- scientists aren't supposed to be afraid of being convinced.
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    Quote Originally Posted by galexander
    Quote Originally Posted by Arcane_Mathematician
    He needs to be banned... Seriously.
    Presumably Arcane_Mathematician you support all forms of media censorship when it comes to anyone with the audacity to express views which contradict the orthodox.

    I suppose countries like Iran must represent an ideal for the likes of yourself. :x
    No. I support the censorship of idiotic ideals that contradict reality. Especially in places where education of sorts take place. I seen no issue with challenging the orthodox views, as is the modus operandi in physics, after all. Einstein challenged newtons laws, and succeeded in proving them not entirely accurate. Newton challenged those before him, and succeeded. All of science is about challenging the accepted view, and demonstrating as well as proving mathematically, that you are right. This has been done at length for Einstein and Newton. What do you have? Nothing. You challenge without any education in the field to speak of, and think yourself the righteous one for going against the established data. You are among the largest detractors of education, because you are willfully ignorant and spread that ignorance to anyone you can. You need to be banned because you don't accept anything that is proven mathematically and demonstrated ad nauseum. When posed a question you can't answer, like so many others who happen to be in the same boat as you with regard to accepted education, you ignore it, and give some bullshit ridiculous question in it's place, or some equally idiotic bullshit unrelated to the question.

    This is why you should be banned, and why you don't belong here. You are a walking contradiction, and you will never understand why.
    Wise men speak because they have something to say; Fools, because they have to say something.
    -Plato

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    Quote Originally Posted by Arcane_Mathematician
    Quote Originally Posted by galexander
    Quote Originally Posted by Arcane_Mathematician
    He needs to be banned... Seriously.
    Presumably Arcane_Mathematician you support all forms of media censorship when it comes to anyone with the audacity to express views which contradict the orthodox.

    I suppose countries like Iran must represent an ideal for the likes of yourself. :x
    No. I support the censorship of idiotic ideals that contradict reality. Especially in places where education of sorts take place. I seen no issue with challenging the orthodox views, as is the modus operandi in physics, after all. Einstein challenged newtons laws, and succeeded in proving them not entirely accurate. Newton challenged those before him, and succeeded. All of science is about challenging the accepted view, and demonstrating as well as proving mathematically, that you are right. This has been done at length for Einstein and Newton. What do you have? Nothing. You challenge without any education in the field to speak of, and think yourself the righteous one for going against the established data. You are among the largest detractors of education, because you are willfully ignorant and spread that ignorance to anyone you can. You need to be banned because you don't accept anything that is proven mathematically and demonstrated ad nauseum. When posed a question you can't answer, like so many others who happen to be in the same boat as you with regard to accepted education, you ignore it, and give some bullshit ridiculous question in it's place, or some equally idiotic bullshit unrelated to the question.

    This is why you should be banned, and why you don't belong here. You are a walking contradiction, and you will never understand why.
    The real problem is Arcane_Mathematician that you will not admit to being wrong because you know how bad the situation is with regard to the physics books being in error.

    It's a veritable House of Cards!

    When Newton was around it was very much early days. 'Science' at the time hardly even existed and Newton himself pretty much came from nowhere. He was an illegitimate son of a farmer who had failed in his career as a shepherd. He also dabbled in all sorts of mysticisms including alchemy and could well have poisoned himself with mercury in the process.

    The problem is therefore that all of modern physics is entirely based upon the musings of one man who could easily have been compared to Harry Potter! :-D
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    Quote Originally Posted by galexander
    Quote Originally Posted by Arcane_Mathematician
    Quote Originally Posted by galexander
    Quote Originally Posted by Arcane_Mathematician
    He needs to be banned... Seriously.
    Presumably Arcane_Mathematician you support all forms of media censorship when it comes to anyone with the audacity to express views which contradict the orthodox.

    I suppose countries like Iran must represent an ideal for the likes of yourself. :x
    No. I support the censorship of idiotic ideals that contradict reality. Especially in places where education of sorts take place. I seen no issue with challenging the orthodox views, as is the modus operandi in physics, after all. Einstein challenged newtons laws, and succeeded in proving them not entirely accurate. Newton challenged those before him, and succeeded. All of science is about challenging the accepted view, and demonstrating as well as proving mathematically, that you are right. This has been done at length for Einstein and Newton. What do you have? Nothing. You challenge without any education in the field to speak of, and think yourself the righteous one for going against the established data. You are among the largest detractors of education, because you are willfully ignorant and spread that ignorance to anyone you can. You need to be banned because you don't accept anything that is proven mathematically and demonstrated ad nauseum. When posed a question you can't answer, like so many others who happen to be in the same boat as you with regard to accepted education, you ignore it, and give some bullshit ridiculous question in it's place, or some equally idiotic bullshit unrelated to the question.

    This is why you should be banned, and why you don't belong here. You are a walking contradiction, and you will never understand why.
    The real problem is Arcane_Mathematician that you will not admit to being wrong because you know how bad the situation is with regard to the physics books being in error.

    It's a veritable House of Cards!

    When Newton was around it was very much early days. 'Science' at the time hardly even existed and Newton himself pretty much came from nowhere. He was an illegitimate son of a farmer who had failed in his career as a shepherd. He also dabbled in all sorts of mysticisms including alchemy and could well have poisoned himself with mercury in the process.

    The problem is therefore that all of modern physics is entirely based upon the musings of one man who could easily have been compared to Harry Potter! :-D
    Dumbass troll is a dumbass... I stand by my statements
    Wise men speak because they have something to say; Fools, because they have to say something.
    -Plato

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    Quote Originally Posted by galexander
    The problem is therefore that all of modern physics is entirely based upon the musings of one man who could easily have been compared to Harry Potter! :-D
    That's a stunningly ignorant claim. Newton developed on the ideas of earlier scientists, who themselves built upon the work of classical natural philosophers. Kepler and Galileo's work predated Newton's birth and both were essential to his own work. I'm sure there were others. Newton may have seen farther than either man, but he built upon pre-existing ideas. It might have taken many more men to do his work had he not done so, but it would have been done. His ideas were then further re-worked by other great minds, most notably Einstein.

    You seem to be trying to put the full burden of modern physics on Newton's shoulders so that you can perform a single, simple character assassination and somehow clear the way for your own ideas. If your ideas are anything like your feeble appraisal of modern physics and your laughably childish tactics, you might as well give it up.
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    Quote Originally Posted by TheBiologista
    Quote Originally Posted by galexander
    The problem is therefore that all of modern physics is entirely based upon the musings of one man who could easily have been compared to Harry Potter! :-D
    That's a stunningly ignorant claim. Newton developed on the ideas of earlier scientists, who themselves built upon the work of classical natural philosophers. Kepler and Galileo's work predated Newton's birth and both were essential to his own work. I'm sure there were others. Newton may have seen farther than either man, but he built upon pre-existing ideas. It might have taken many more men to do his work had he not done so, but it would have been done. His ideas were then further re-worked by other great minds, most notably Einstein.

    You seem to be trying to put the full burden of modern physics on Newton's shoulders so that you can perform a single, simple character assassination and somehow clear the way for your own ideas. If your ideas are anything like your feeble appraisal of modern physics and your laughably childish tactics, you might as well give it up.
    Wrong.

    You are simply repeating the stereotyped, populist view of Newton, TheBiologista. Ever read an accurate biography of Newton? I suspect not.

    If you check out the biographical detail Newton plagiarised other person's ideas such as Robert Hook and it is doubtful he founded calculus single-handedly either.

    In Newton's time the 'scientific method' was still very much in its infant years.

    You wouldn't make a good historian TheBioligista.
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    The validity of any aspect of physics or any other science is not based on the character of particular scientists, but on how well hypotheses agree with experimental results.
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    Quote Originally Posted by jsloan
    The validity of any aspect of physics or any other science lies in how well hypotheses agree with experimental results, not in the character of any of its practitioners.
    But what if the whole thing falls apart on paper?

    When this is the case are we to trust the experimenters?
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    Quote Originally Posted by galexander
    Quote Originally Posted by jsloan
    The validity of any aspect of physics or any other science lies in how well hypotheses agree with experimental results, not in the character of any of its practitioners.
    But what if the whole thing falls apart on paper?

    When this is the case are we to trust the experimenters?
    No. Absolutely not.

    When this is the case, we repeat the experiments for ourselves, and then re-repeat them, and then repeat them some more, untill there is no reasonable doubt that the original results are correct (or, indeed, not correct).
    "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair." ~ Douglas Adams
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    Quote Originally Posted by galexander
    But what if the whole thing falls apart on paper?

    When this is the case are we to trust the experimenters?
    What we do, as drowsy turtle mentioned, is try and repeat the experiment to get the same results. If the experimental results are repeatable and consistent, then we have to revise theory to agree with those results. It doesn't matter how elegant a hypothesis is on paper. If it doesn't agree with experimental results it has to be changed.
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    Quote Originally Posted by galexander
    Quote Originally Posted by jsloan
    The validity of any aspect of physics or any other science lies in how well hypotheses agree with experimental results, not in the character of any of its practitioners.
    But what if the whole thing falls apart on paper?

    When this is the case are we to trust the experimenters?
    Nothing has fallen apart on paper unless it is your grade on a physics test.
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    Quote Originally Posted by jsloan
    Quote Originally Posted by galexander
    But what if the whole thing falls apart on paper?

    When this is the case are we to trust the experimenters?
    What we do, as drowsy turtle mentioned, is try and repeat the experiment to get the same results. If the experimental results are repeatable and consistent, then we have to revise theory to agree with those results. It doesn't matter how elegant a hypothesis is on paper. If it doesn't agree with experimental results it has to be changed.
    Then show us all those experimental results which you have been so good as to quote. :?
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    Quote Originally Posted by galexander
    Quote Originally Posted by jsloan
    Quote Originally Posted by galexander
    But what if the whole thing falls apart on paper?

    When this is the case are we to trust the experimenters?
    What we do, as drowsy turtle mentioned, is try and repeat the experiment to get the same results. If the experimental results are repeatable and consistent, then we have to revise theory to agree with those results. It doesn't matter how elegant a hypothesis is on paper. If it doesn't agree with experimental results it has to be changed.
    Then show us all those experimental results which you have been so good as to quote. :?
    Turn on a light switch in your house. If it works, that confirms Newton's laws which have been used for two or three centuries to build things like turbines and generators. Turn on your GPS. It works because Newton's laws were used to put the satellites in orbit. Is that good enough for you?
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    Quote Originally Posted by Harold14370
    Quote Originally Posted by galexander
    Quote Originally Posted by jsloan
    Quote Originally Posted by galexander
    But what if the whole thing falls apart on paper?

    When this is the case are we to trust the experimenters?
    What we do, as drowsy turtle mentioned, is try and repeat the experiment to get the same results. If the experimental results are repeatable and consistent, then we have to revise theory to agree with those results. It doesn't matter how elegant a hypothesis is on paper. If it doesn't agree with experimental results it has to be changed.
    Then show us all those experimental results which you have been so good as to quote. :?
    Turn on a light switch in your house. If it works, that confirms Newton's laws which have been used for two or three centuries to build things like turbines and generators. Turn on your GPS. It works because Newton's laws were used to put the satellites in orbit. Is that good enough for you?
    No, it's not.

    I want to see that the equations work in detail and that they ALL balance using the relevant experimentally determined physical quantities. :wink:
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  82. #81  
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    Quote Originally Posted by galexander
    Quote Originally Posted by TheBiologista
    Quote Originally Posted by galexander
    The problem is therefore that all of modern physics is entirely based upon the musings of one man who could easily have been compared to Harry Potter! :-D
    That's a stunningly ignorant claim. Newton developed on the ideas of earlier scientists, who themselves built upon the work of classical natural philosophers. Kepler and Galileo's work predated Newton's birth and both were essential to his own work. I'm sure there were others. Newton may have seen farther than either man, but he built upon pre-existing ideas. It might have taken many more men to do his work had he not done so, but it would have been done. His ideas were then further re-worked by other great minds, most notably Einstein.

    You seem to be trying to put the full burden of modern physics on Newton's shoulders so that you can perform a single, simple character assassination and somehow clear the way for your own ideas. If your ideas are anything like your feeble appraisal of modern physics and your laughably childish tactics, you might as well give it up.
    Wrong.

    You are simply repeating the stereotyped, populist view of Newton, TheBiologista. Ever read an accurate biography of Newton? I suspect not.

    If you check out the biographical detail Newton plagiarised other person's ideas such as Robert Hook and it is doubtful he founded calculus single-handedly either.

    In Newton's time the 'scientific method' was still very much in its infant years.

    You wouldn't make a good historian TheBioligista.
    My point was that Newton did not change the face of physics (or science) by himself and that a character assassination won't really serve your cause. You sneer at that point and 'counter' that he plagiarized other people's work... wait now how does that counter my point? It doesn't. I might not make a particularly good historian, but I'll take that over bafflingly bad logic.
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    Quote Originally Posted by galexander
    Quote Originally Posted by Harold14370
    Quote Originally Posted by galexander
    Quote Originally Posted by jsloan
    Quote Originally Posted by galexander
    But what if the whole thing falls apart on paper?

    When this is the case are we to trust the experimenters?
    What we do, as drowsy turtle mentioned, is try and repeat the experiment to get the same results. If the experimental results are repeatable and consistent, then we have to revise theory to agree with those results. It doesn't matter how elegant a hypothesis is on paper. If it doesn't agree with experimental results it has to be changed.
    Then show us all those experimental results which you have been so good as to quote. :?
    Turn on a light switch in your house. If it works, that confirms Newton's laws which have been used for two or three centuries to build things like turbines and generators. Turn on your GPS. It works because Newton's laws were used to put the satellites in orbit. Is that good enough for you?
    No, it's not.

    I want to see that the equations work in detail and that they ALL balance using the relevant experimentally determined physical quantities. :wink:
    Then run an experiment. High school physics classes have you run experiments to show that Newton's laws hold true, and when I ran the experiments, I found that the results were very close to newtons predicted results. Error in the results being caused by both human error and the limitations of the measuring devices at hand.
    Wise men speak because they have something to say; Fools, because they have to say something.
    -Plato

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    Quote Originally Posted by galexander
    Then show us all those experimental results which you have been so good as to quote. :?
    I didn't quote any experimental results in this thread, but I'll give you an example you should be able to relate to.

    Hypothesis: the continents on Earth are not moving.

    Experimental results: meaurements from satellites and ground stations show that continents move a measureable amount (in centimeters) each year. This is a fact.

    So, since experiments show that the continents are moving the hypothesis that they are not moving is wrong and has to be rejected.
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    Quote Originally Posted by TheBiologista
    Quote Originally Posted by galexander
    Quote Originally Posted by TheBiologista
    Quote Originally Posted by galexander
    The problem is therefore that all of modern physics is entirely based upon the musings of one man who could easily have been compared to Harry Potter! :-D
    That's a stunningly ignorant claim. Newton developed on the ideas of earlier scientists, who themselves built upon the work of classical natural philosophers. Kepler and Galileo's work predated Newton's birth and both were essential to his own work. I'm sure there were others. Newton may have seen farther than either man, but he built upon pre-existing ideas. It might have taken many more men to do his work had he not done so, but it would have been done. His ideas were then further re-worked by other great minds, most notably Einstein.

    You seem to be trying to put the full burden of modern physics on Newton's shoulders so that you can perform a single, simple character assassination and somehow clear the way for your own ideas. If your ideas are anything like your feeble appraisal of modern physics and your laughably childish tactics, you might as well give it up.
    Wrong.

    You are simply repeating the stereotyped, populist view of Newton, TheBiologista. Ever read an accurate biography of Newton? I suspect not.

    If you check out the biographical detail Newton plagiarised other person's ideas such as Robert Hook and it is doubtful he founded calculus single-handedly either.

    In Newton's time the 'scientific method' was still very much in its infant years.

    You wouldn't make a good historian TheBioligista.
    My point was that Newton did not change the face of physics (or science) by himself and that a character assassination won't really serve your cause. You sneer at that point and 'counter' that he plagiarized other people's work... wait now how does that counter my point? It doesn't. I might not make a particularly good historian, but I'll take that over bafflingly bad logic.
    What I was saying The Bioligista was that if everything I said about Newton was historical, biographical fact, how can that count as character assassination?

    You are the one who is following baffling bad logic.
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    Quote Originally Posted by Arcane_Mathematician
    Quote Originally Posted by galexander
    Quote Originally Posted by Harold14370
    Quote Originally Posted by galexander
    Quote Originally Posted by jsloan
    Quote Originally Posted by galexander
    But what if the whole thing falls apart on paper?

    When this is the case are we to trust the experimenters?
    What we do, as drowsy turtle mentioned, is try and repeat the experiment to get the same results. If the experimental results are repeatable and consistent, then we have to revise theory to agree with those results. It doesn't matter how elegant a hypothesis is on paper. If it doesn't agree with experimental results it has to be changed.
    Then show us all those experimental results which you have been so good as to quote. :?
    Turn on a light switch in your house. If it works, that confirms Newton's laws which have been used for two or three centuries to build things like turbines and generators. Turn on your GPS. It works because Newton's laws were used to put the satellites in orbit. Is that good enough for you?
    No, it's not.

    I want to see that the equations work in detail and that they ALL balance using the relevant experimentally determined physical quantities. :wink:
    Then run an experiment. High school physics classes have you run experiments to show that Newton's laws hold true, and when I ran the experiments, I found that the results were very close to newtons predicted results. Error in the results being caused by both human error and the limitations of the measuring devices at hand.
    Please quote detail about the experiments in question.

    How can we pay close attention to what is little more than a passing comment, opinion?
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    Quote Originally Posted by jsloan
    Quote Originally Posted by galexander
    Then show us all those experimental results which you have been so good as to quote. :?
    I didn't quote any experimental results in this thread, but I'll give you an example you should be able to relate to.

    Hypothesis: the continents on Earth are not moving.

    Experimental results: meaurements from satellites and ground stations show that continents move a measureable amount (in centimeters) each year. This is a fact.

    So, since experiments show that the continents are moving the hypothesis that they are not moving is wrong and has to be rejected.
    And what in the world has this got to do with Isaac Newton
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    Quote Originally Posted by galexander
    Quote Originally Posted by jsloan
    Quote Originally Posted by galexander
    Then show us all those experimental results which you have been so good as to quote. :?
    I didn't quote any experimental results in this thread, but I'll give you an example you should be able to relate to.

    Hypothesis: the continents on Earth are not moving.

    Experimental results: meaurements from satellites and ground stations show that continents move a measureable amount (in centimeters) each year. This is a fact.

    So, since experiments show that the continents are moving the hypothesis that they are not moving is wrong and has to be rejected.
    And what in the world has this got to do with Isaac Newton
    I believe it was an example of the scientific method being used to reject an incorrect hypothesis.

    ... The insinuation being, that you should use a similar method to attempt to disprove whatever laws/constants you are trying to attack (I can't even remember what your point was supposed to be).
    "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair." ~ Douglas Adams
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    Quote Originally Posted by galexander
    Quote Originally Posted by Arcane_Mathematician
    Quote Originally Posted by galexander
    Quote Originally Posted by Harold14370
    Quote Originally Posted by galexander
    Quote Originally Posted by jsloan
    Quote Originally Posted by galexander
    But what if the whole thing falls apart on paper?

    When this is the case are we to trust the experimenters?
    What we do, as drowsy turtle mentioned, is try and repeat the experiment to get the same results. If the experimental results are repeatable and consistent, then we have to revise theory to agree with those results. It doesn't matter how elegant a hypothesis is on paper. If it doesn't agree with experimental results it has to be changed.
    Then show us all those experimental results which you have been so good as to quote. :?
    Turn on a light switch in your house. If it works, that confirms Newton's laws which have been used for two or three centuries to build things like turbines and generators. Turn on your GPS. It works because Newton's laws were used to put the satellites in orbit. Is that good enough for you?
    No, it's not.

    I want to see that the equations work in detail and that they ALL balance using the relevant experimentally determined physical quantities. :wink:
    Then run an experiment. High school physics classes have you run experiments to show that Newton's laws hold true, and when I ran the experiments, I found that the results were very close to newtons predicted results. Error in the results being caused by both human error and the limitations of the measuring devices at hand.
    Please quote detail about the experiments in question.

    How can we pay close attention to what is little more than a passing comment, opinion?
    how about you do a google search, "simple experiments to verify Newton's laws" for simple experiments used to verify Newtons laws...
    Wise men speak because they have something to say; Fools, because they have to say something.
    -Plato

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  90. #89  
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    Quote Originally Posted by galexander
    Quote Originally Posted by TheBiologista
    Quote Originally Posted by galexander
    Quote Originally Posted by TheBiologista
    Quote Originally Posted by galexander
    The problem is therefore that all of modern physics is entirely based upon the musings of one man who could easily have been compared to Harry Potter! :-D
    That's a stunningly ignorant claim. Newton developed on the ideas of earlier scientists, who themselves built upon the work of classical natural philosophers. Kepler and Galileo's work predated Newton's birth and both were essential to his own work. I'm sure there were others. Newton may have seen farther than either man, but he built upon pre-existing ideas. It might have taken many more men to do his work had he not done so, but it would have been done. His ideas were then further re-worked by other great minds, most notably Einstein.

    You seem to be trying to put the full burden of modern physics on Newton's shoulders so that you can perform a single, simple character assassination and somehow clear the way for your own ideas. If your ideas are anything like your feeble appraisal of modern physics and your laughably childish tactics, you might as well give it up.
    Wrong.

    You are simply repeating the stereotyped, populist view of Newton, TheBiologista. Ever read an accurate biography of Newton? I suspect not.

    If you check out the biographical detail Newton plagiarised other person's ideas such as Robert Hook and it is doubtful he founded calculus single-handedly either.

    In Newton's time the 'scientific method' was still very much in its infant years.

    You wouldn't make a good historian TheBioligista.
    My point was that Newton did not change the face of physics (or science) by himself and that a character assassination won't really serve your cause. You sneer at that point and 'counter' that he plagiarized other people's work... wait now how does that counter my point? It doesn't. I might not make a particularly good historian, but I'll take that over bafflingly bad logic.
    What I was saying The Bioligista was that if everything I said about Newton was historical, biographical fact, how can that count as character assassination?
    That's not what you were saying. First, you stated that the problem with modern physics was that it was based upon the ideas of a person of whom you have a poor opinion. Since you're offering an alternative viewpoint to the consensus on modern physics, your likely motive was to smear an entire field of research by association with a person of whom you have a poor opinion. I pointed out that modern physics is not based on that person's work alone (however he might be characterized). I noted that the true responsibility for modern physics is dispersed amongst many people and thus your negative appraisal of one person does not really constitute a 'problem' with modern physics (besides which, a negative appraisal of character is irrelevant to the credibility of the field). Then you made a statement which further dispersed responsibility for modern physics amongst other people, undermining your initial claim regarding 'the problem' with modern physics and reiterating the point I'd only just made. I pointed this out, in response to which you claimed your appraisal was factual.

    You're now saying you were not engaging in a character assassination. If we assume your appraisal of Newton is fully accurate then I guess that's true. But at best, it'd still be an ad hominem argument, and a weak one that you undermined all by yourself.

    Quote Originally Posted by galexander
    You are the one who is following baffling bad logic.
    Yeah okay. To be honest, if you really can't see it, there's not a thing anyone here can do for you.
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    Quote Originally Posted by drowsy turtle
    Quote Originally Posted by galexander
    Quote Originally Posted by jsloan
    Quote Originally Posted by galexander
    Then show us all those experimental results which you have been so good as to quote. :?
    I didn't quote any experimental results in this thread, but I'll give you an example you should be able to relate to.

    Hypothesis: the continents on Earth are not moving.

    Experimental results: meaurements from satellites and ground stations show that continents move a measureable amount (in centimeters) each year. This is a fact.

    So, since experiments show that the continents are moving the hypothesis that they are not moving is wrong and has to be rejected.
    And what in the world has this got to do with Isaac Newton
    I believe it was an example of the scientific method being used to reject an incorrect hypothesis.

    ... The insinuation being, that you should use a similar method to attempt to disprove whatever laws/constants you are trying to attack (I can't even remember what your point was supposed to be).
    Unfortunately I do not have access to a physics laboratory to carry out your suggestion.
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    Quote Originally Posted by Arcane_Mathematician
    Quote Originally Posted by galexander
    Quote Originally Posted by Arcane_Mathematician
    Quote Originally Posted by galexander
    Quote Originally Posted by Harold14370
    Quote Originally Posted by galexander
    Quote Originally Posted by jsloan
    Quote Originally Posted by galexander
    But what if the whole thing falls apart on paper?

    When this is the case are we to trust the experimenters?
    What we do, as drowsy turtle mentioned, is try and repeat the experiment to get the same results. If the experimental results are repeatable and consistent, then we have to revise theory to agree with those results. It doesn't matter how elegant a hypothesis is on paper. If it doesn't agree with experimental results it has to be changed.
    Then show us all those experimental results which you have been so good as to quote. :?
    Turn on a light switch in your house. If it works, that confirms Newton's laws which have been used for two or three centuries to build things like turbines and generators. Turn on your GPS. It works because Newton's laws were used to put the satellites in orbit. Is that good enough for you?
    No, it's not.

    I want to see that the equations work in detail and that they ALL balance using the relevant experimentally determined physical quantities. :wink:
    Then run an experiment. High school physics classes have you run experiments to show that Newton's laws hold true, and when I ran the experiments, I found that the results were very close to newtons predicted results. Error in the results being caused by both human error and the limitations of the measuring devices at hand.
    Please quote detail about the experiments in question.

    How can we pay close attention to what is little more than a passing comment, opinion?
    how about you do a google search, "simple experiments to verify Newton's laws" for simple experiments used to verify Newtons laws...
    The URL you quote is not specific enough by anyone's standards.
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    Quote Originally Posted by TheBiologista
    Quote Originally Posted by galexander
    Quote Originally Posted by TheBiologista
    Quote Originally Posted by galexander
    Quote Originally Posted by TheBiologista
    Quote Originally Posted by galexander
    The problem is therefore that all of modern physics is entirely based upon the musings of one man who could easily have been compared to Harry Potter! :-D
    That's a stunningly ignorant claim. Newton developed on the ideas of earlier scientists, who themselves built upon the work of classical natural philosophers. Kepler and Galileo's work predated Newton's birth and both were essential to his own work. I'm sure there were others. Newton may have seen farther than either man, but he built upon pre-existing ideas. It might have taken many more men to do his work had he not done so, but it would have been done. His ideas were then further re-worked by other great minds, most notably Einstein.

    You seem to be trying to put the full burden of modern physics on Newton's shoulders so that you can perform a single, simple character assassination and somehow clear the way for your own ideas. If your ideas are anything like your feeble appraisal of modern physics and your laughably childish tactics, you might as well give it up.
    Wrong.

    You are simply repeating the stereotyped, populist view of Newton, TheBiologista. Ever read an accurate biography of Newton? I suspect not.

    If you check out the biographical detail Newton plagiarised other person's ideas such as Robert Hook and it is doubtful he founded calculus single-handedly either.

    In Newton's time the 'scientific method' was still very much in its infant years.

    You wouldn't make a good historian TheBioligista.
    My point was that Newton did not change the face of physics (or science) by himself and that a character assassination won't really serve your cause. You sneer at that point and 'counter' that he plagiarized other people's work... wait now how does that counter my point? It doesn't. I might not make a particularly good historian, but I'll take that over bafflingly bad logic.
    What I was saying The Bioligista was that if everything I said about Newton was historical, biographical fact, how can that count as character assassination?
    That's not what you were saying. First, you stated that the problem with modern physics was that it was based upon the ideas of a person of whom you have a poor opinion. Since you're offering an alternative viewpoint to the consensus on modern physics, your likely motive was to smear an entire field of research by association with a person of whom you have a poor opinion. I pointed out that modern physics is not based on that person's work alone (however he might be characterized). I noted that the true responsibility for modern physics is dispersed amongst many people and thus your negative appraisal of one person does not really constitute a 'problem' with modern physics (besides which, a negative appraisal of character is irrelevant to the credibility of the field). Then you made a statement which further dispersed responsibility for modern physics amongst other people, undermining your initial claim regarding 'the problem' with modern physics and reiterating the point I'd only just made. I pointed this out, in response to which you claimed your appraisal was factual.

    You're now saying you were not engaging in a character assassination. If we assume your appraisal of Newton is fully accurate then I guess that's true. But at best, it'd still be an ad hominem argument, and a weak one that you undermined all by yourself.

    Quote Originally Posted by galexander
    You are the one who is following baffling bad logic.
    Yeah okay. To be honest, if you really can't see it, there's not a thing anyone here can do for you.
    The problem is the figure of Newton has become the subject of idol worship and people are genuinely shocked and refuse to believe the biographical reality of who the man really was.

    But once you've heard the whole truth there's no big whizz to it at all.

    I'm no character assassin. :x
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    Quote Originally Posted by galexander
    Quote Originally Posted by TheBiologista
    Quote Originally Posted by galexander
    Quote Originally Posted by TheBiologista
    Quote Originally Posted by galexander
    Quote Originally Posted by TheBiologista
    Quote Originally Posted by galexander
    The problem is therefore that all of modern physics is entirely based upon the musings of one man who could easily have been compared to Harry Potter! :-D
    That's a stunningly ignorant claim. Newton developed on the ideas of earlier scientists, who themselves built upon the work of classical natural philosophers. Kepler and Galileo's work predated Newton's birth and both were essential to his own work. I'm sure there were others. Newton may have seen farther than either man, but he built upon pre-existing ideas. It might have taken many more men to do his work had he not done so, but it would have been done. His ideas were then further re-worked by other great minds, most notably Einstein.

    You seem to be trying to put the full burden of modern physics on Newton's shoulders so that you can perform a single, simple character assassination and somehow clear the way for your own ideas. If your ideas are anything like your feeble appraisal of modern physics and your laughably childish tactics, you might as well give it up.
    Wrong.

    You are simply repeating the stereotyped, populist view of Newton, TheBiologista. Ever read an accurate biography of Newton? I suspect not.

    If you check out the biographical detail Newton plagiarised other person's ideas such as Robert Hook and it is doubtful he founded calculus single-handedly either.

    In Newton's time the 'scientific method' was still very much in its infant years.

    You wouldn't make a good historian TheBioligista.
    My point was that Newton did not change the face of physics (or science) by himself and that a character assassination won't really serve your cause. You sneer at that point and 'counter' that he plagiarized other people's work... wait now how does that counter my point? It doesn't. I might not make a particularly good historian, but I'll take that over bafflingly bad logic.
    What I was saying The Bioligista was that if everything I said about Newton was historical, biographical fact, how can that count as character assassination?
    That's not what you were saying. First, you stated that the problem with modern physics was that it was based upon the ideas of a person of whom you have a poor opinion. Since you're offering an alternative viewpoint to the consensus on modern physics, your likely motive was to smear an entire field of research by association with a person of whom you have a poor opinion. I pointed out that modern physics is not based on that person's work alone (however he might be characterized). I noted that the true responsibility for modern physics is dispersed amongst many people and thus your negative appraisal of one person does not really constitute a 'problem' with modern physics (besides which, a negative appraisal of character is irrelevant to the credibility of the field). Then you made a statement which further dispersed responsibility for modern physics amongst other people, undermining your initial claim regarding 'the problem' with modern physics and reiterating the point I'd only just made. I pointed this out, in response to which you claimed your appraisal was factual.

    You're now saying you were not engaging in a character assassination. If we assume your appraisal of Newton is fully accurate then I guess that's true. But at best, it'd still be an ad hominem argument, and a weak one that you undermined all by yourself.

    Quote Originally Posted by galexander
    You are the one who is following baffling bad logic.
    Yeah okay. To be honest, if you really can't see it, there's not a thing anyone here can do for you.
    The problem is the figure of Newton has become the subject of idol worship and people are genuinely shocked and refuse to believe the biographical reality of who the man really was.
    How can that be a problem with modern physics if, by your admission, Newton is not responsible for modern physics?

    Quote Originally Posted by galexander
    But once you've heard the whole truth there's no big whizz to it at all.
    What the hell are you talking about?

    Quote Originally Posted by galexander
    I'm no character assassin. :x
    I don't think you know what you are or what you're doing.
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    Quote Originally Posted by galexander
    The problem is the figure of Newton has become the subject of idol worship and people are genuinely shocked and refuse to believe the biographical reality of who the man really was.

    But once you've heard the whole truth there's no big whizz to it at all.

    I'm no character assassin. :x
    Anyone who has actually learned some physics knows that Newton is a big whizz. But if you can prove that it was actually Hooke who is responsible for Newton's work, then I will take down my shrine to Newton and put one up to Hooke. Hooke was actually pretty good in his own right, anyway.
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  96. #95  
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    Quote Originally Posted by galexander
    Unfortunately I do not have access to a physics laboratory to carry out your suggestion.
    You don't need an expensive laboratory to test key aspects of Newtonian Gravitation. I'm pretty sure you could get fairly accurate measurements of 'g' using a golf ball, a flight of stairs, and a stop watch, for instance. You could then use this value to test against the predicted value of 'g' at the Earth's surface (typically around 9.8 m/s^2, but you could calculate the predicted value from your altitude and lattitude if you wanted, assuming an even mass distribution within the Earth).

    Just off the top of my head. If you don't like this, design your own experiment. If it makes sense and actually has promise, you'll find lots of people are willing to test it. If it's fucktarded, scientists will tend to ignore you.



    FYI, ignorantly posting about how wrong the established laws of physics are counts as fucktarded.
    "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair." ~ Douglas Adams
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  97. #96  
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    Quote Originally Posted by galexander
    Quote Originally Posted by Arcane_Mathematician
    Quote Originally Posted by galexander
    Quote Originally Posted by Arcane_Mathematician
    Quote Originally Posted by galexander
    Quote Originally Posted by Harold14370
    Quote Originally Posted by galexander
    Quote Originally Posted by jsloan
    Quote Originally Posted by galexander
    But what if the whole thing falls apart on paper?

    When this is the case are we to trust the experimenters?
    What we do, as drowsy turtle mentioned, is try and repeat the experiment to get the same results. If the experimental results are repeatable and consistent, then we have to revise theory to agree with those results. It doesn't matter how elegant a hypothesis is on paper. If it doesn't agree with experimental results it has to be changed.
    Then show us all those experimental results which you have been so good as to quote. :?
    Turn on a light switch in your house. If it works, that confirms Newton's laws which have been used for two or three centuries to build things like turbines and generators. Turn on your GPS. It works because Newton's laws were used to put the satellites in orbit. Is that good enough for you?
    No, it's not.

    I want to see that the equations work in detail and that they ALL balance using the relevant experimentally determined physical quantities. :wink:
    Then run an experiment. High school physics classes have you run experiments to show that Newton's laws hold true, and when I ran the experiments, I found that the results were very close to newtons predicted results. Error in the results being caused by both human error and the limitations of the measuring devices at hand.
    Please quote detail about the experiments in question.

    How can we pay close attention to what is little more than a passing comment, opinion?
    how about you do a google search, "simple experiments to verify Newton's laws" for simple experiments used to verify Newtons laws...
    The URL you quote is not specific enough by anyone's standards.
    I quoted a google search... it was meant to be non-specific you nitwit. I even stated it was a google search. Can you not even read what I write?
    Wise men speak because they have something to say; Fools, because they have to say something.
    -Plato

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  98. #97  
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    Quote Originally Posted by drowsy turtle
    Quote Originally Posted by galexander
    Unfortunately I do not have access to a physics laboratory to carry out your suggestion.
    You don't need an expensive laboratory to test key aspects of Newtonian Gravitation. I'm pretty sure you could get fairly accurate measurements of 'g' using a golf ball, a flight of stairs, and a stop watch, for instance. You could then use this value to test against the predicted value of 'g' at the Earth's surface (typically around 9.8 m/s^2, but you could calculate the predicted value from your altitude and lattitude if you wanted, assuming an even mass distribution within the Earth).

    Just off the top of my head. If you don't like this, design your own experiment. If it makes sense and actually has promise, you'll find lots of people are willing to test it. If it's fucktarded, scientists will tend to ignore you.



    FYI, ignorantly posting about how wrong the established laws of physics are counts as fucktarded.
    Oh, brilliant example of an experiment to prove Newton correct drowsey turtle, oh wise one!

    The only problem is this thread is about conservation of momentum and kinetic energy NOT the value of the acceleration due to gravity.

    Wake up would you and pay attention.
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  99. #98  
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    It's all gone a bit quiet!

    Is everyone still there?

    Have I said something wrong by any chance?
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  100. #99  
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    Since you lot have gone a bit silent I can only assume that at last you have admitted defeat.................!! :-D

    Sweet glory indeed.........!

    I can now retire from this thread knowing I have made my point.
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  101. #100  
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    Quote Originally Posted by quackxander
    Since you lot have gone a bit silent I can only assume that at last you have admitted defeat.................!!
    Quote Originally Posted by drowsy turtle
    FYI, ignorantly posting about how wrong the established laws of physics are counts as fucktarded.
    Quote Originally Posted by trollboy
    Sweet glory indeed.........!
    Quote Originally Posted by Me
    Oh yes, Mightily Glorious King of all Fucktards.
    Quote Originally Posted by Mightily Glorious King of all Fucktards
    I can now retire from this thread knowing I have made my point.
    Quote Originally Posted by Me
    Please retire from the forum. Thanks.
    I was some of the mud that got to sit up and look around.
    Lucky me. Lucky mud.
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    Cat's Cradle.
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