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Thread: vacuums

  1. #1 vacuums 
    Forum Masters Degree organic god's Avatar
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    can someone explain to me how a vacuum works. i looked on wikipedia and got confused so i came here so someone could give me a basic explanation.

    i understand that a vacuum is an abscene of matter. and that there is no such thing as a perfect vacuum.

    i was curious as to how one creates a vacuum, and also the applications of it.

    did an experiment with my sink where i filled a glass with water, turned it upside down whilst it was in a sin full of water and then pulled it out. i felt resistance as i tried to remove it from the water. is this due to a vacuum.

    one final question - how does vacuum suction work, when using a buchner funnel for example, how does running water create a suction mechanism =S.

    sorry for the long post


    everything is mathematical.
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  3. #2 Re: vacuums 
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    Quote Originally Posted by organic god
    can someone explain to me how a vacuum works. i looked on wikipedia and got confused so i came here so someone could give me a basic explanation.

    i understand that a vacuum is an abscene of matter. and that there is no such thing as a perfect vacuum.

    i was curious as to how one creates a vacuum, and also the applications of it.

    did an experiment with my sink where i filled a glass with water, turned it upside down whilst it was in a sin full of water and then pulled it out. i felt resistance as i tried to remove it from the water. is this due to a vacuum.

    one final question - how does vacuum suction work, when using a buchner funnel for example, how does running water create a suction mechanism =S.

    sorry for the long post
    Up until recently the older paint spray guns used vacuum to pull paint from the cup below. By blowing air at a high velocity passed, and around, another orifice, you can create a vacuum in that other orifice. Today many guns are top feed.

    When setting up a refrigeration system, you must vacuum out the system, to boil off water and even oil, that is in a system. As well as remove all the ambient air that has gotten into the system while you are piping it.

    There are different types of pumps. Some are dry pumps, with graphite veins. Some have other types of fiber reinforced resin based veins that are run wet, in oil. The pump makes a little vapor and some of the vapor is oil.

    Some devices that you can connect to a regular air compressor, use the vacuum created by the air pressure, to create an icing effect on one side of the device and a red glowing coil at the other side. All done with air pressure, and a very small air flow. If I get a chance I will find it and film it.

    You can never get all the air out of a chamber. The metal walls of the chamber will evaporate into the vacuum, before you get there. But you can remove actually, probably over half of the air in the chamber.

    I was watching some high speed video of inert gas in a plasma state. And some of the atoms or molecules of the inert gas, appeared to expand to the size of a very large pin head. That is under ARC conditions, probably the most excited you will get to see atoms here on earth. Yet, in a vacuum I highly doubt the atoms are that expanded.

    Most regular vacuums use centrifuge action to pump air. The blades on the centrifuge pumps, spinning pump plate face, are curved to reduce noise and harmonics.

    Sincerely,


    William McCormick


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  4. #3  
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    Maybe I can help. You can imagine the air or any other gas as an entity of small gas particles (atoms or molecules). Depending on the temperature, they move around on random paths. If you put it in a box, these particle hit the walls and produce a force, a thrust, against them. Now, if you have a wall separating two boxes of different pressure (i.e. different number of particles per volume), then the gas with the higher pressure can produce a stronger thrust than the other, just because there are more particles hitting it. This is observed as a force trying to pull something into the gas with a lower pressure. And an extreme low pressure is commonly called vacuum.

    Interestingly, you can increase the pressure of the initially low-pressure gas by increasing its temperature. This increases the velocity of the individual particles which in summary leads to a stronger thrust on the wall.
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  5. #4 Re: vacuums 
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    Quote Originally Posted by organic god
    did an experiment with my sink where i filled a glass with water, turned it upside down whilst it was in a sin full of water and then pulled it out. i felt resistance as i tried to remove it from the water. is this due to a vacuum.
    No, not vacuum. This is due to atmospheric pressure on the surface of the water in the sink. It’s the principle of the Torricelli barometer.
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    i felt resistance as i tried to remove it from the water. is this due to a vacuum.
    No, not vacuum. This is due to gravity. You'd feel the same 'resistance' even if the container was sealed with a lid. But it is true that the Toricelli principle is what keeps the water in the glass.

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  7. #6 Re: vacuums 
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    Quote Originally Posted by JaneBennet
    Quote Originally Posted by organic god
    did an experiment with my sink where i filled a glass with water, turned it upside down whilst it was in a sin full of water and then pulled it out. i felt resistance as i tried to remove it from the water. is this due to a vacuum.
    No, not vacuum. This is due to atmospheric pressure on the surface of the water in the sink. It’s the principle of the Torricelli barometer.
    Wouldn't the force that held the glass to the water. Be that molecules of water tend to cling to one another. And the force of capillarity. A sudden pull would have to break a lot of bonds of the water, at once to pull away from the surface.

    The vacuum in the cup that remains until air is allowed to get into the cup. Is what keeps the water from leaving the cup.

    If you move the cup up slowly you can let air get into the cup and it will instantly get lighter.

    I tried it, and found that even though the cup is slightly above the surface, the bonds of the water do not let go. And it appears these bonds are what causes the cup to feel heavy, even though it is no longer below the surface.

    I also used a cup with a hole in it. And you can just raise it up, if you take your finger off the hole, allow air to get into it.


    Would anyone like to hear how ambient radiation would play into this?



    Sincerely,


    William McCormick
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  8. #7  
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    Quote Originally Posted by SteveF
    You'd feel the same 'resistance' even if the container was sealed with a lid.
    I doubt it. If the mouth of the glass is sealed, you should be able to lift the glass clean out of the water without resistance.
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    Quote Originally Posted by JaneBennet
    Quote Originally Posted by SteveF
    You'd feel the same 'resistance' even if the container was sealed with a lid.
    I doubt it. If the mouth of the glass is sealed, you should be able to lift the glass clean out of the water without resistance.
    Well, the resistance is nothing more than the weight of the water in the cup anyway, which is being held up inside the cup by atmospheric pressure. When the cup is lifted out of the water, a bubble of air can now get up into the cup, the pressure on the column of water equalizes, and it falls out of the cup making it lighter.

    I think it is best not to think of vacuum as an entity in itself. The forces you sense are just the forces of atmospheric pressure.
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  10. #9  
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    Quote Originally Posted by Harold14370
    I think it is best not to think of vacuum as an entity in itself. The forces you sense are just the forces of atmospheric pressure.
    I concur. The notion of a vacuum is a useful concept but beware of reifying it.
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  11. #10  
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    I did not say anything about a vacuum.
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    Quote Originally Posted by JaneBennet
    I did not say anything about a vacuum.
    Right, you didn't. That part of my post was directed at the OP.
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  13. #12  
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    That was what I thought. :-D
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  14. #13  
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    Quote Originally Posted by organic god
    did an experiment with my sink where i filled a glass with water, turned it upside down whilst it was in a sin full of water and then pulled it out. i felt resistance as i tried to remove it from the water. is this due to a vacuum.
    I took a second look at what you are describing and the best explanation is just the weight of the glass and the water in the glass which you are lifting is the only downward force your are feeling. The reason that that you feel this downward force increasing is because there is an upward force that is decreasing as you pull the glass out of the water. This is the bouyancy force. For a ping pong ball this force is enough to make the ball float on the water but for the glass that force is still there even if it is not enough to make the glass float.

    But if you are asking why the water stays in the cup then you could say that vacuum is an issue. I mean JaneBennet is correct in saying that it is due to the atmospheric pressure which is due to gravity acting on the atmosphere. But on the other hand we could also say this is an issue of gauge pressure and og's experiment creates a negative gauge pressure inside the cup at the top of the water, so you can indeed say that without that negative gauge pressure (or vacuum) there would be no force keeping the water in the glass.
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  15. #14  
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    OK, here's a simple and interesting thought experiment on this topic. You have a container filled with water and sealed with a thin paper or plastic lid. The container is inverted over a tank of water so that the lid is slightly below the surface. The container is attached to a spring balance to measure the force/weight needed to support the filled container.

    Since the container is sealed, I hope we all agree the the spring balance is measuring only the pull of gravity. There can be no vacuum or atmospheric pressure contributions.

    Now the lid is punctured. Atmospheric pressure and/or vacuum can now play a role. Even capillary action and molecular attraction can be invoked if you wish.

    Here is your question: would the spring balance measure a difference in force or would it show the same reading as before the puncture?

    Greater, lesser, or the same?

    (Everyone can play.)
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  16. #15  
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    Quote Originally Posted by SteveF
    OK, here's a simple and interesting thought experiment on this topic. You have a container filled with water and sealed with a thin paper or plastic lid. The container is inverted over a tank of water so that the lid is slightly below the surface. The container is attached to a spring balance to measure the force/weight needed to support the filled container.

    Since the container is sealed, I hope we all agree the the spring balance is measuring only the pull of gravity.
    That's right. Gotcha.

    Quote Originally Posted by SteveF
    There can be no vacuum or atmospheric pressure contributions.

    Now the lid is punctured. Atmospheric pressure and/or vacuum can now play a role. Even capillary action and molecular attraction can be invoked if you wish.

    Here is your question: would the spring balance measure a difference in force or would it show the same reading as before the puncture?

    Greater, lesser, or the same?
    Same of course.

    However lowering the whole thing into the water would decrease the spring balance measure because of the increasing bouyancy force upward on the glass.
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    Quote Originally Posted by SteveF
    Greater, lesser, or the same?
    *
    If the lid is stiff and cannot flex, my vote is that the spring scale reads a little lighter, but only by a RCH. (R stands for "red" hair which is a little finer.)
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    Quote Originally Posted by JaneBennet
    I did not say anything about a vacuum.
    You are right, there is actually no force sucking the water into the glass.

    However, the fact that there is a vacuum of air, in the glass, the water cannot leave the glass. As Long as there is atmospheric pressure.

    Even if we did this experiment in a vacuum you would see that the water in the glass would still remain a certain level above the pool of water it was immersed in. Proving there is no such thing as a perfect vacuum. If water did not boil off.

    In day to day life we pull vacuums with pumps and other equipment and watch the water or fluid levels go up. But it is just the fact that the air is evacuated and there is no more counter pressure to keep the water from rising.

    That is good scientific observation though. Why can't you apply that to the sub-atomic world?


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    William McCormick
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    Quote Originally Posted by mitchellmckain
    Quote Originally Posted by organic god
    did an experiment with my sink where i filled a glass with water, turned it upside down whilst it was in a sin full of water and then pulled it out. i felt resistance as i tried to remove it from the water. is this due to a vacuum.
    I took a second look at what you are describing and the best explanation is just the weight of the glass and the water in the glass which you are lifting is the only downward force your are feeling. The reason that that you feel this downward force increasing is because there is an upward force that is decreasing as you pull the glass out of the water. This is the bouyancy force. For a ping pong ball this force is enough to make the ball float on the water but for the glass that force is still there even if it is not enough to make the glass float.

    But if you are asking why the water stays in the cup then you could say that vacuum is an issue. I mean JaneBennet is correct in saying that it is due to the atmospheric pressure which is due to gravity acting on the atmosphere. But on the other hand we could also say this is an issue of gauge pressure and og's experiment creates a negative gauge pressure inside the cup at the top of the water, so you can indeed say that without that negative gauge pressure (or vacuum) there would be no force keeping the water in the glass.
    That is a good point too. When you go to pick up the cup. And break the seal below, you cannot just pull the water out of that little difference in height above the pool. There is no basis for flow. The water has no reason to come out of the glass yet. Capillarity and molecular bonds are holding it there.

    As you mentioned you get a negative pressure, created in the cup. That would mean that suddenly, external pressure would press down on the cup.

    Also a very good observation.

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    William McCormick
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  20. #19  
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    All right, I’ve thought about this again, and I’ve come to the conclusion that atmospheric pressure probably doesn’t play any part in resisting the pulling of the container out of water. All that the atmospheric pressure is doing is maintaining the Torricelli effect – i.e. keeping the upside-down container filled with water when the (uncapped) mouth of the container is under water. Instead the resistance might be due to the force required to break the intermolecular forces between the water in the container and the water in the sink. It should thus be clear why sealing the mouth of the container with an impervious cap should make it easier to lift the container out of the water.

    For the record, I’ve just gone and done an experiment myself using a plastic milk bottle with a cap. I admit that I hardly felt any difference between when the cap was on and when the cap was removed. This might be because the extra force needed to separate the intermolecular forces in the water is too small to be felt. Or it might be because I didn’t use a large enough bottle.
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    Quote Originally Posted by JaneBennet
    All right, I’ve thought about this again, and I’ve come to the conclusion that atmospheric pressure probably doesn’t play any part in resisting the pulling of the container out of water. All that the atmospheric pressure is doing is maintaining the Torricelli effect – i.e. keeping the upside-down container filled with water when the (uncapped) mouth of the container is under water. Instead the resistance might be due to the force required to break the intermolecular forces between the water in the container and the water in the sink. It should thus be clear why sealing the mouth of the container with an impervious cap should make it easier to lift the container out of the water.

    For the record, I’ve just gone and done an experiment myself using a plastic milk bottle with a cap. I admit that I hardly felt any difference between when the cap was on and when the cap was removed. This might be because the extra force needed to separate the intermolecular forces in the water is too small to be felt. Or it might be because I didn’t use a large enough bottle.
    You were right the first time.
    It does keep the weight of the water as the weight of the water, pressed equally to the glass, and the glass equally pressed to the water.

    But as you pass the point, that the cup can no longer contain the water, the water tries to escape from the cup. You loose the pool pressure the water is creating in the pool at the surface.

    That instantly creates a vacuum of air inside the cup, and creates pressure on the outside of the cup.

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    As you pull the inverted glass up out of the water, you are lifting a column of water of increasing height, thus the glass gets heavier the further you lift it. Another way of saying this same thing is that the top of the water column is at a lower pressure than the water surface, and the outside air, by an amount rho*g*h This results in a difference in pressure between the inside and outside of the glass and a downward force on the glass.

    When air is allowed to rush up into the glass, the vaccum is broken and the water falls out. You feel a release of the weight. It is this sudden release of force which you perceive as an extra resistance at the end. There isn't really any resistance.
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    Quote Originally Posted by Harold14370
    As you pull the inverted glass up out of the water, you are lifting a column of water of increasing height, thus the glass gets heavier the further you lift it. Another way of saying this same thing is that the top of the water column is at a lower pressure than the water surface, and the outside air, by an amount rho*g*h This results in a difference in pressure between the inside and outside of the glass and a downward force on the glass.

    When air is allowed to rush up into the glass, the vaccum is broken and the water falls out. You feel a release of the weight. It is this sudden release of force which you perceive as an extra resistance at the end. There isn't really any resistance.
    At the surface of the water, you have more then atmospheric pressure. Because the water is not just held down by the atmospheric pressure. It is also held down by gravity. Its specific gravity is greater then that of air.

    So at the moment you let the seal break, you allow the column of water to pull the glass down, with the total weight of the water contained in the glass.
    While the glass was in the pool, it was suspended by the pool pressure. Once the seal is broken it is only suspended by the atmospheric pressure and gains weight, through the vacuum created, by the water falling. And by the pressure on the outside of the glass.

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  24. #23  
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    Quote Originally Posted by Harold14370
    As you pull the inverted glass up out of the water, you are lifting a column of water of increasing height, thus the glass gets heavier the further you lift it. Another way of saying this same thing is that the top of the water column is at a lower pressure than the water surface, and the outside air, by an amount rho*g*h This results in a difference in pressure between the inside and outside of the glass and a downward force on the glass.
    The problem with this explanation, or you could say what adds a degree of puzzlement is that you are not directly lifting up the water as would be the case if the cup is right side up. There is no glass pushing the water up. Instead it is the atmospheric pressure relative to the pressure at the top of the water in the glass that make the water move up with the glass. But if you are not actually lifting the water but that the atmosphere is doing the lifting, then why do you feel the weight of the water as you lift the glass? It is because of the pressure difference on the top of the glass, which being created by the weight of the water that is lifted, is therefore going to create a downward force on the glass equal to the weight of the water.

    Now isn't that curious? For we come full circle and come to the conclusion that the answer to the question in the OP is actually YES. The downward force being a product of the negative gauge pressure in the cup is therefore indeed a product of a vacuum effect. LOL


    So what difference does covering the opening of the glass make? Well there are cases where there is a difference. For example, if the glass we are talking about is over 10 meters tall, then something different will happen when we lift the glass past the 10 meter mark because at that point the atmospheric pressure will not be enough to lift any more water. In which case the uncovered glass will have a space appear above the water in the glass which will not be perfect vacuum because it will fill with water vapor. That means that in the case of the covered glass on a scale, if we poke a hole in the covered glass then water will leak out until you have only a 10 meter height of water in the glass and that means the measure on the scale will decrease from its starting point.



    PS. This thread has been a wonderful demonstration about how the simplest physics sometimes requires very careful thinking. LOL
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  25. #24  
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    Quote Originally Posted by Harold14370
    It is this sudden release of force which you perceive as an extra resistance at the end.
    I didn't feel "resistance" personally. But something else threw me off: visual observation. As the water spilled I saw the glass rim dip again beneath the surface. Apparently some force was pulling the glass down. In fact, the water level in the sink was rising.
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    Quote Originally Posted by William McCormick
    At the surface of the water, you have more then atmospheric pressure. Because the water is not just held down by the atmospheric pressure. It is also held down by gravity. Its specific gravity is greater then that of air.
    William McCormick
    No, sir, you are wrong. At the surface of the water in the sink, you have atmospheric pressure exactly. It cannot possibly be otherwise. At the top surface of the water column, where it touches the bottom of the glass, there is less than atmospheric pressure. The difference from the top of the water column to the bottom is rho g h.
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    Quote Originally Posted by William McCormick
    So at the moment you let the seal break, you allow the column of water to pull the glass down, with the total weight of the water contained in the glass.
    While the glass was in the pool, it was suspended by the pool pressure. Once the seal is broken it is only suspended by the atmospheric pressure and gains weight, through the vacuum created, by the water falling. And by the pressure on the outside of the glass.
    The equillibrium physics was hard enough, don't you think?

    It seems that there must be a continuous transition from the weight of the water and the glass together to the weight of the glass alone and from my explanation above we can see why. The transition time is the time it takes for the pressure at the top inside of the glass to return to atmospheric. Because of pressure, the water cannot fall straight down, so the air must move upward in the glass to dispace the water.
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  28. #27 vacuum is a kind of space time configuration 
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    vacuum is a kind of space time configuration(STC) in the universe , which is consists of product of an coefficient ( |G|=6.67259e-11) and volume unit , that is , STC of vacuum =|G|m^3 .

    Main function of vacuum is to substantiate and materialize informtion of the universe emerging all thing happening in the universe(including the
    event of you are reading this short message itself) .

    Actually , for every physical unit , there inherently exist its STC in nature , e.g.

    STC of kglogram = |G|m^3s^-2

    STC of Joule = |G|m^5s^-4

    STC of Ampere = √|G| m^3 s^-3

    See more detailed at :
    http://www.universefedback.com/Spiri...e_Universe.htm
    http://www.universefedback.com/Spiri...e_Universe.htm
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  29. #28 Re: vacuum is a kind of space time configuration 
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    There's that word again:
    Quote Originally Posted by zhang zhi qiang
    Actually
    What does it mean? :wink:
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    Quote Originally Posted by Harold14370
    Quote Originally Posted by William McCormick
    At the surface of the water, you have more then atmospheric pressure. Because the water is not just held down by the atmospheric pressure. It is also held down by gravity. Its specific gravity is greater then that of air.
    William McCormick
    No, sir, you are wrong. At the surface of the water in the sink, you have atmospheric pressure exactly. It cannot possibly be otherwise. At the top surface of the water column, where it touches the bottom of the glass, there is less than atmospheric pressure. The difference from the top of the water column to the bottom is rho g h.
    You have the air pressure pushing down on the water, as well as the water itself, having its own specific gravity, giving it pressure above that of air pressure at the surface.

    It is like that Jello 123, that forms stratified layers in a glass. There is more pressure at the surface of each dense layer then the one above it. That is why it forms a stratified structure.

    I used to program the computer for the hazardous waste plant, and we would do the conversions from gallons to pounds. Using the specific gravity of whatever goo we were describing. I had a lot of practice with specific gravity.

    If the water was not more dense and heavy, when a gentle five mile an hour wind blew on it, it would swirl up like wind does. There is a tremendous difference in specific gravity between water and air. It is an infinite ratio, 1/0, with water being given a unity value of one. And air not registering or being accounted for in most things being weighed.

    If you vacuum out a sealed container you could probably on a triple beam scale read the difference.

    I know what you mean though, over the years of working with things in the current standards, you find yourself thinking in terms of the standard. I had a little trouble with the upside down glass myself. And I should not.

    But I work with the common terms all the time. And I don't always do a total conversion. I too often just use the standard. It is dangerous though.

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    William McCormick
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    Quote Originally Posted by mitchellmckain
    Quote Originally Posted by William McCormick
    So at the moment you let the seal break, you allow the column of water to pull the glass down, with the total weight of the water contained in the glass.
    While the glass was in the pool, it was suspended by the pool pressure. Once the seal is broken it is only suspended by the atmospheric pressure and gains weight, through the vacuum created, by the water falling. And by the pressure on the outside of the glass.
    The equillibrium physics was hard enough, don't you think?
    I dropped out of school when I was fifteen and went to work full time. I worked very hard, learning anything I could about anything I could. I met some people that were the top individuals in their field.

    I would ask them how their stuff works, and I would try to use some of the terms the current physics people use, so as not to scare them off.

    But sometimes I would meet someone that I knew right away was a Universal Scientist trained guy, and he would grab something and demonstrate it to me in ten seconds. Something that I see people studying for a lifetime. And stat all the hype was for job security.


    So I don't really know anything about modern physics. I may use some of the same useful things or terms, that may also be contained in modern physics. But I am a Universal Science guy.

    From everything I saw, there is no other way, but to have a Universal Understanding.
    In my travels I would meet top individuals from all the different fields of science. I would discuss science with them. And they would jump up sometimes as I would tell them why I could not understand something. I would use analogies from one field to the next, highlighting hypocritical use of the same product. They would jump up because they could not believe that another field was using something so obviously dangerous in some apparatus. This happened to me many, many times.

    Sometimes the scientists really would not know, that nitrogen was actually used in fire extinguishers. Because they thought nitrogen was some kind of explosive. Probably leading them to the conclusion that ammonia is NH3 rather then NO2

    I believe what happens with most current scientists is that they do not understand explosives. Explosives do not have to burn in order to create a bomb. Liquid nitrogen can be shocked and create a powerful explosion, with magnetic fields. If a core is detonated in it. So can any noble gas.

    This was misunderstood by the best current scientists, and have lead them to misunderstandings about flammability, verses shocking.

    Sincerely,


    William McCormick
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  32. #31 Re: vacuum is a kind of space time configuration 
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    Quote Originally Posted by Pong
    There's that word again:
    Quote Originally Posted by zhang zhi qiang
    Actually
    What does it mean? :wink:
    The word ACTUALLY, although it means "in fact", has become, of a lack of facts. Come to mean the present belief.

    Years ago, I believe that ACTUALLY was a more exacting word. And did not just mean that because it was in a book or some new idea existed, that it was ACTUALLY so. But rather something that you could prove right now.






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    William McCormick
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  33. #32  
    Forum Radioactive Isotope mitchellmckain's Avatar
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    Quote Originally Posted by William McCormick
    Quote Originally Posted by Harold14370
    Quote Originally Posted by William McCormick
    At the surface of the water, you have more then atmospheric pressure. Because the water is not just held down by the atmospheric pressure. It is also held down by gravity. Its specific gravity is greater then that of air.
    William McCormick
    No, sir, you are wrong. At the surface of the water in the sink, you have atmospheric pressure exactly. It cannot possibly be otherwise. At the top surface of the water column, where it touches the bottom of the glass, there is less than atmospheric pressure. The difference from the top of the water column to the bottom is rho g h.
    You have the air pressure pushing down on the water, as well as the water itself, having its own specific gravity, giving it pressure above that of air pressure at the surface.
    Ok I am going to step between you guys. For a solid, gravity acts on the whole object with one force because of the cohesive forces holding solid to together. This is true up to a limit because if enough mass and gravity is involved even solids begin to take on some of the aspects of a liquid. It is just that it takes a lot more pressure before it becomes significant in comparison to the elastic (compression) modulus and to the shear modulus. This why when solid bodies in space reach a certain size, their self-gravitation makes them assume a spherical shape.

    Likewise we can say by extention that the forces holding the water together like the surface tension, Van der Waals, and viscosity does transmit some nearly insignificant portion of the gravitational force on the water to act on the surface of the water. It is kind of like grabing the bottom of a globule of water in free fall and being able to pull the whole thing IF you do not use an acceleration high enough that cohesive forces of the water are exceeded.

    However, is this force really significant compared to the pressure differences in water? Well beads of water on a smooth surface kind of show just how significant this is for we see that these beads of water are about a milimeter in thickness, which means these cohesive forces are significant over a pressure differences of about 10 Pascals or .0001 atm.
    See my physics of spaceflight simulator at http://www.relspace.astahost.com

    I now have a blog too: http://astahost.blogspot.com/
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  34. #33  
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    Quote Originally Posted by William McCormick
    I dropped out of school when I was fifteen and went to work full time.
    You don't say.
    Probably leading them to the conclusion that ammonia is NH3 rather then NO2
    Imagine that.
    Liquid nitrogen can be shocked and create a powerful explosion, with magnetic fields. If a core is detonated in it. So can any noble gas.
    That I would like to see. Do you think you could give the chemical formula for that reaction?
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  35. #34  
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    Quote Originally Posted by Harold14370
    Quote Originally Posted by William McCormick
    I dropped out of school when I was fifteen and went to work full time.
    You don't say.
    Probably leading them to the conclusion that ammonia is NH3 rather then NO2
    Imagine that.
    Liquid nitrogen can be shocked and create a powerful explosion, with magnetic fields. If a core is detonated in it. So can any noble gas.
    That I would like to see. Do you think you could give the chemical formula for that reaction?
    There is not really a reaction, except in the sense of atomically splitting the Siamese pair of atoms as it used to be called.

    When you separate two atoms of nitrogen, you get energy absorbed. When they come together they release heat.

    It is similar to atomic welding or plasma cutting. When done with pure hydrogen it is called atomic hydrogen welding.



    http://www.Rockwelder.com/EastWood/weldarticle.pdf

    It is also the principle of the explosives that cause massive town wide destruction. Caused almost always by the misunderstanding between flammable and shocked, explosives. A very common accident. Some of the best scientists I have met did not understand this principle. It was tucked away that well. After the town suffers one of these explosions. The town realizes that no one wants to talk about it. It is one of those taboo things.

    Whenever a core is shielded by, or in a totally hermetic casing. The casing must either give way, shatter, tear, or break. And release pressure. Or something else happens, to the casing. It becomes a part of the core and bomb.

    Some cores like liquid cores cannot just tear. If you have ever done a belly flop from a high distance, you know that you probably wish, the water would have given or torn. To ease that hard skin reddening slap you get, from hitting the surface of water dead flat on.

    So when you super charge a liquid with voltage, from an internal electrochemical reaction. The only way to power the reaction is from the outside of the core, with ambient radiation.

    As the ambient radiation slows to destructive speeds and velocity. Like a super gravity ray. The liquid is often super heated, super pressurized and sometimes splits, from its Siamese bond with itself.
    This delays explosion further, while absorbing energy. But in the end the energy is just stored, and is dissipated during the expansion of the super high voltage hemispherical cloud of atomically reacting gas.

    That is why when the law makers talk of nuclear weapons we think they are just insane. There really are no such thing. We can do much worse with conventional elements.

    The real bomb dropped on Hiroshima was actually a liquid state change bomb. Its duplicate resided at West Point into the seventies. It was on display there and was stated to be the duplicate of the actual bomb dropped on Hiroshima. This bomb used a 22 pound hammer sensing device to detonate the ammonium nitrate core.

    It was decided to hide this bomb by some fools. Because obviously if you are pretty handy, you know that all these principles are part and parcel of everyday life. And to hide them is to condemn others to death. Play God if you will.



    http://www.Rockwelder.com/Explosives...imahalfton.PDF

    Full article below.

    Incidentally this bomb has been around since World War One.

    The Germans used a limited atomic explosive. The oil filled Flack shell in World War Two.

    Sincerely,


    William McCormick
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  36. #35  
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    Quote Originally Posted by Harold14370
    Quote Originally Posted by William McCormick
    I dropped out of school when I was fifteen and went to work full time.
    You don't say.
    Probably leading them to the conclusion that ammonia is NH3 rather then NO2
    Imagine that.
    Liquid nitrogen can be shocked and create a powerful explosion, with magnetic fields. If a core is detonated in it. So can any noble gas.
    That I would like to see. Do you think you could give the chemical formula for that reaction?
    Did you see the Super (Edited Future) Weapon show, where Mac and the English mad scientist, show off a water cased bomb they use to knock down a wall.

    The reason they use a liquid is because it takes time to change a liquids direction more so then a solid. Almost like a gyro type of energy. The liquid first absorbs energy before it moves. That takes time, that creates staying power.

    Need a laugh. I made this for my father. To take his keg down the basement steps. It works well. The next model will have a grab handle on it. I plan to send one to my Uncle, a retired Gunny Sergeant.

    We loaned it to the Greek church near me for the festival, and they want one too.

    http://www.Rockwelder.com/Flash/x29/x29.html

    If you see Mac from Future Weapons, I deny I made this video or that I know anything about it. Ha-ha.



    Sincerely,


    William McCormick
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  37. #36  
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    Quote Originally Posted by mitchellmckain
    Quote Originally Posted by William McCormick
    Quote Originally Posted by Harold14370
    Quote Originally Posted by William McCormick
    At the surface of the water, you have more then atmospheric pressure. Because the water is not just held down by the atmospheric pressure. It is also held down by gravity. Its specific gravity is greater then that of air.
    William McCormick
    No, sir, you are wrong. At the surface of the water in the sink, you have atmospheric pressure exactly. It cannot possibly be otherwise. At the top surface of the water column, where it touches the bottom of the glass, there is less than atmospheric pressure. The difference from the top of the water column to the bottom is rho g h.
    You have the air pressure pushing down on the water, as well as the water itself, having its own specific gravity, giving it pressure above that of air pressure at the surface.
    Ok I am going to step between you guys. For a solid, gravity acts on the whole object with one force because of the cohesive forces holding solid to together. This is true up to a limit because if enough mass and gravity is involved even solids begin to take on some of the aspects of a liquid. It is just that it takes a lot more pressure before it becomes significant in comparison to the elastic (compression) modulus and to the shear modulus. This why when solid bodies in space reach a certain size, their self-gravitation makes them assume a spherical shape.

    Likewise we can say by extention that the forces holding the water together like the surface tension, Van der Waals, and viscosity does transmit some nearly insignificant portion of the gravitational force on the water to act on the surface of the water. It is kind of like grabing the bottom of a globule of water in free fall and being able to pull the whole thing IF you do not use an acceleration high enough that cohesive forces of the water are exceeded.

    However, is this force really significant compared to the pressure differences in water? Well beads of water on a smooth surface kind of show just how significant this is for we see that these beads of water are about a milimeter in thickness, which means these cohesive forces are significant over a pressure differences of about 10 Pascals or .0001 atm.
    Look at mercury in a vacuum. You could put a piece of aluminum on it and it would float. Yet nearly no atmospheric pressure.

    As soon as you touch the surface of the mercury, you have pressure, pushing up against the bottom of whatever you are floating on it. Or sinking into it. The specific gravity of mercury is 13.6 and will float a lot of common metals. I do not believe that mercury vapor will put substantial pressure on the mercury. However it is a variable.


    Just like CO2 gas will float a balloon filled with air.

    The water in the upside down glass, either has to raise the water from the pool of water. Or break the seal at the surface. Which it does. While the seal is breaking you feel the suction or better put the pressure on the outside of the glass. Pushing it to the water.



    Sincerely,


    William McCormick
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  38. #37 Let's seek fact 
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    Every physical unit (dimA) inherently has its own space time structure , so called sapce time configuraton (STC) , and can be expressed in an universal formula as :

    dimA =Bm^a s^-b
    here ,B is cofficient ,B≥|G|=6.67259e-11 .
    a ,b =5,4,3,2,1 ,0 ,-1,-2,-3,-4,-5 (whole number)
    m represents one dimensional space ,
    s expresses one dimensional time .

    Also dimA has its space time value (STV) .e.g.

    STV(m)=2.4686279637116245…e+34
    STV(s) =0.7400760451286427…e+43

    These conclusions are obtained based on observed datum established in
    physics for hundreds years , they are fundamental physical constants :
    G = |G| m^3 kg^-1 s^-2 =6.67259e-11 m^3 kg^-1 s^-2
    h = |h| J s =6.6260755e-34 J s
    c = |c| m s^-1 =2.99792458e+8ms^-1
    k(B)=| k(B)| J / K =1.380658e-23JK^-1
    plus 4 Planck dimensions (Planck mass , length , time and temperature).

    STC and STV for all physical units can be calculated out and turn up as same manner as above formula .

    From calculations results , we can get another conclusion as follow :
    The universe is composed of 5 dimensional space and 5 dimensional time.

    Of course , you can absolutely deny this argument if you can search out
    an physical unit whose number of a or b in its STC is larger than 5 .

    If all people on this planet can not find such exceptional physical unit , then you , everyone on the earth , must accept this fact that the universe we live has 5 dimensions of space and 5 dimensions of time , since the universe is composed of nothing but various phyiscal quantities (physical units) .

    See more detailed at :

    Axiom of Physics / G Gauge
    http://www.universefedback.com/popularized_e/c1.htm

    Multidimensional Space Time
    http://www.universefedback.com/popularized_e/c2.htm















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