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About LinkBacksCan energy and matter exist in the same place at the same time?
August 3rd, 2011, 03:39 AM
Can energy and matter exist in the same place at the same time?
As matter can have energy I'd say yes, the vibration that atoms natural go through are caused my it having energy
Matter only turns into energy if it goes into another region of space.
Huh? What does that mean? Atoms vibrate and the strength of these vibrations is termed thermal energyOriginally Posted by Geo
That doesn't make much sense really- could you explain what you mean further?
[QUOTE=Nevyn;277523]A stone of sixty degrees celsius thrown in a pan of boiling water cools the water. Thrown in water of twenty degrees celsius it warms the water. What implications does that have for (the general idea of) "thermic energy of the stone" (or molecules) ?
[QUOTE=Ghrasp;277528]The internal energy of the stone is given byA stone of sixty degrees celsius thrown in a pan of boiling water cools the water. Thrown in water of twenty degrees celsius it warms the water. What implications does that have for (the general idea of) "thermic energy of the stone" (or molecules) ?
this means that the internal energy of a material/substance is equal to the sum of the total kinetic and potential energy of the atoms in the substance. So, when you put the stone into something which cools it down- then the kinetic energy of the particles inside the stone will decrease (as temperature is just a measure of how fast particles are moving), decreasing the internal energy as a whole- and conversely, if you heat the stone, kinetic energy will increase thus increasing internal energy.
[QUOTE=Ghrasp;277528]The stone, when placed into the boiling water, will cool the water but the temperature of the stone will also increase as the energy in the system spreads out in an attempt to reach equilibrium. Same for when it is placed in the cold water.A stone of sixty degrees celsius thrown in a pan of boiling water cools the water. Thrown in water of twenty degrees celsius it warms the water. What implications does that have for (the general idea of) "thermic energy of the stone" (or molecules) ?
The stone has a certain amount of thermal energy (kinetic energy of the atoms) and if this is placed in a medium cooler than itself the medium will take some of this kinetic energy the atoms reach a single uniform(ish) kinetic energy.
[QUOTE=x(x-y);277531]The internal energy of the stone is given byA stone of sixty degrees celsius thrown in a pan of boiling water cools the water. Thrown in water of twenty degrees celsius it warms the water. What implications does that have for (the general idea of) "thermic energy of the stone" (or molecules) ?
this means that the internal energy of a material/substance is equal to the sum of the total kinetic and potential energy of the atoms in the substance. So, when you put the stone into something which cools it down- then the kinetic energy of the particles inside the stone will decrease (as temperature is just a measure of how fast particles are moving), decreasing the internal energy as a whole- and conversely, if you heat the stone, kinetic energy will increase thus increasing internal energy.
The delusion of absoluteness comes from the Kelvin scale. It goes from an absolute cold. But an absolute cold what ? For a stone or an absolute cold in general ?
An absolutely cold stone (or near to that temperature) actually has a huge energypotential for cooling fridges maybe for a whole city. The colder it gets the more potential energy it will have. Negative and positive are only for the use you would make of it in the technical sense. It,s clearly negative energy for warming houses in the winter or for an oven. But thermic energy to an absolute cold as a general notion (where everything would be absolutely cold) is big nonsense. It has to be to the same stone in an absolute cold state at another time or a comparable stone at same time (but different place). Then compare between these states ; what happens between the two different (similar) stones or what happened to the same stone in time.
The thermic energy that can be related to a K temperature is the energy difference between these two states for the same stone (at different time) not related to a zero thermic energy in general as for everything including all thermometers. A difference has the same unity as what the difference is between. Just as six [apples] minus four [apples] means two [apples] for difference. Meassured for one basket of apples, four disappeared but only to the basket not in general.
No, a cold stone does not have huge potential energy to cool things. It is, however a large heat sink which can drain heat from objects which have large potential heat energy. And it is this movement of heat energy which does work.
An icecold stone thrown in a bucket of water can,t cool and freeze water ?
I think it can and the energy is between the water and the stone. That means the stone must also be part of the potential for heath. After this the change of energy for te water ecquals approx the change of energy for the stone. It,s no longer near zero kelvin but warmed up. The change is what matters as E=P*t. If the stone was isolated to a hotter environment t will be longer and P lower but that has nothing to do with eventuell energychange but the rate of change P. Isolation or not makes no difference for the potential energy.
What do you mean with sink ? Of temperature or heath ? Like a lower altitude as a sink or a downhill drive ? Going to a lower altitude is a sink to me but not the altitude itself.
Cooling a stone to near zero every next degree sink (decrease of temperature) will take more energy but that energy is not the energy that is taken out of the stone it is the energy that is needed to do this in a hotter environment. Allready while sinking the temperature for the stone there is an opposite heath from environment with higher temperature to the stone. To lower a degree on any scale that heat has to be compensated first by the cooling machine and it will increase for every next degree the lower the temperature becomes. But the energy the cooling machine pumps is not the energy taken from the stone it,s just the energy needed ; the compensation plus the extra to cool further. The lower the temperature becomes the higher this energy is to even out the heath from the environment to the stone.
Keeping a stone at 10 K constant temperature allready needs a significant constant cooling that means heath from stone to environment and energy for the coolingmachine to pump heath from the stone.
Just as a fridge is a heathpump from inside (including things inside) to outside. If inside remains at a constant temperature it means that the heath inside (air as well as things inside) to outside from the pump balances out the heath trough the walls and door. Balances out as in compensates (they don,t annihilate or something) because the directions are opposite.
So when an object radiates infrared heat energy into space and the object cools down, it is actually space which has the potential energy to cool off the object ????
You have a very poor understanding of thermodynamics, among other things.
No, The icecold stone doesn't cool the water, the water warms the stone. Heat moves from hot to cold, a cold object has less and because of this any warmer object that it comes in contact with will allow some of its energy to flow to the cold object till they are the same temperature.An icecold stone thrown in a bucket of water can,t cool and freeze water ?
I think it can and the energy is between the water and the stone. That means the stone must also be part of the potential for heath. After this the change of energy for te water ecquals approx the change of energy for the stone. It,s no longer near zero kelvin but warmed up. The change is what matters as E=P*t. If the stone was isolated to a hotter environment t will be longer and P lower but that has nothing to do with eventuell energychange but the rate of change P. Isolation or not makes no difference for the potential energy.
THIS DOES NOT WORK THE OTHER WAY ROUND. Cold does not travel to hot as cold is just an abscence of hot. Darkness is an abscence of light in the same way that cold is an abscence of heat
Now you use the argument I first made against me ? Going in cirkles there ?
So you don't know any thermodynamics and can't recognize sarcasm when it bites your ass.
I can even recognize a failed attempt of being sarcastic. Didn,t you recognize you got it back ? You get it back for a better try or think of something else instead of being sarcastic.
Basically, Ghrasp, what you need to understand is that colder substances have a lower internal energy than hotter substances due to their smaller kinetic energy and smaller potential energy. Cold substances do not have a high potential energy to cool down hotter substances, it is the other way around- the hotter substances have a high potential energy to transer their heat towards the colder one, which will thus reduce the temperature of the hotter item and increase the temperature of the colder one- the system will attempt to reach a state of equilibrium.
Thermal dynamics can be difficult to understand. From the perspective of a human who wants to get electricity out of it, the stone at zero kelvin represents a cold sink, which when paired with a hot object, allows electricity to be retrieved from the hot object's heat. This is an entropy question, though, not an energy question. Electricity in a power line is energy at low entropy, whereas raw heat is energy at high entropy. The cold object isn't adding to the system's energy at all. It's just making more of that energy available for use.
Again something is subscribed to me that can,t be read from my posts (or it can as it shows but that,s bad reading then).Cold substances do not have a high potential energy to cool down hotter substances
A warm pan of water put in a fridge would result in a cooler fridge on the inside and the water getting hotter. If such thing is somewhere in my posts (or could be read like that somewhere) be welcome to point me at it.
Don,t underestimate the heath for cooling engines (or steamengines) lengthwise through the pipes. This limits the temperature differences that can be reached because when they get higher this leaking increases. It,s leaking for the purpose, and loss for fuell but it is heath just the same and this leaking has nothing to do with entropy, it is part of the mechanic build ; the pipes have to be conductive for heath. The idea of a sink is not in place because of this.
And please : heath doesn,t transfer heath or hot. Thats similar language as"a falling fall" or "a falling high". Or energy that transfers heath or heath tranferring energy. Heath is a form of energy and is transfer. Or a transfer would transfer transfer.
Last edited by Ghrasp; August 5th, 2011 at 11:03 AM.
Mass represents a predictable amount of energy, whether it is moving or not (which is frame dependent), and no matter what temperature it may register. Even at Absolute Zero (no measurable temperature) the mass still represents a predictable amount of energy.
Not only can matter and energy occupy the same place at the same time, that pretty much is the definition of matter.
Hopefully, you are not being serious here.
No, in thermodynamics, Q represents the addition of heat to a system (heat flow/transfer)- if you just wanted to talk about heat as in "how hot something is" then you would just use T (temperature).
The increment in internal energy of a system is equal to the increment of heat supplied to the system (heat transfer) minus the work done by the system on its surroundings:
I don't know if Ghrasp is having trouble communicating his ideas to us ( language problem ), or if he simply doesn't grasp ( he-he, a pun ) what we're trying to tell him.
In daily life in English isn,t heath more as P=E/t. Intensity is an implicit factor for heath not necessarilly for warmth. Energy hasn,t got that intensity implicit and as far as I know (learned during my study) Q hasn,t got that implicit either. Warmte is as far as I know the dutch word for Q in technical books. In English that would be warmth.
One of my schoolbooks for technics literally had "warmteleer" on the cover. Warmte for English, American language I would use the word warmth not heath.
A bigger size amount same temperature also implies more warmth but making anything hotter.
Same size higher temperature more hot also means more warmth.
To put it bland :
"With a cup of coffee in a bathtub with 50 deg.Celsius water, the water in the bathtub has more warmth (warmte in Dutch) then the cup of coffee but the coffee is hotter or more hot.
Heath from where less warmth to more warmth is very well possible then or someone could not burn himself to a cup of coffee.
If I remember well I always studied these books with the idea Q was for warmth. Heath as dQ/t there. The coffee is less warmth then the water in a bathtub with 40 degree and heath with dQ as negative is very well possible then between two systems.
Otherwise there wouldn,t be fridges (or steamengines) either.
dU=dQ-dW. The loss of a fridge or steamengine is not only dW to the outside there is a huge internal loss as well through the metals between different parts (part where condensation takes place and part where expansion/evaporation takes place).
For the flame that drives the steamengine this is work that is not related to the outside of the steamengine.
And also dQ has same unity as Q and W and dW. Therefor DU also has energy as unity. It would only be about warmth then.
Checked the idea of Q for warmte on the dutch wikipage (my books are old) and it still says Q for warmte there not for heath.
So it seems to be not just me or what is all this ?
Q for warmth or for heath ? Energy or intensity ? And if Q is for heath then what sign is for warmth ?
Heath is dWarmth makes no sense because heath is also dependant of distance for radiation.
No, P = E/t is simply the formula for power as it is energy per unit time (N m s-1)- power is not the same as heat. Heat transfer, with the symbol Q, has the units N m and so is just energy. If you were talking about heat transfer rate then you would have
No, one of the modern definitions of heat in thermodynamics is "The energy transferred from a high-temperature system to a lower-temperature system is called heat".
Warmth is not a physical quantity, and as shown above- heat is just Q not, the latter would be the time derivative of heat transfer.
As explained earlier, Q is heat transfer with the units of energy. It is not intensity as intensity has the units W m-2, these are the units for something called heat flux which is defined as the rate of heat transfer per unit cross-sectional area.
I hope you realise that the term "dW" in the equation
does not mean "dWarmth", -dW means the work done by the system on it's surroundings in this case- it also has the units of energy (J = N m) as the equation must be homogenous.
In Dutch for thermodynamica (or "warmteleer") it is still Q (warmte) warmte (Q) and German : wärme (Q), Q ( wärme) no matter what level of education.
Any translator English to Dutch for any book would obviously translate :
Heat --hitte, warmth - warmte.
But for fysics books :
heat...warmte
warmth..hitte.
If that,s confusing it,s not my fault, it,s how it seems to be.
I don't really see the point you're trying to make, that's just a matter of language and differing translations- nothing to do with the actual physics of thermodynamics.
If everytime you see a Q in a formula book you,re mind reads heat or warmth ? Or it would be simply Q no matter what it means, stands for or comes from.
That sure makes a huge difference for learning, studying (in general : thinking) and reflecting on things. Fysics and daily life are not real seperate worlds. It interact with the use of the words, reading, listening.
Take any book of literature for example and change the word warmth consecquently to heat or heat to warmth. That maybe hot literature (and the dutch book cosy ) but offcourse it affects the book for what it is and does with reading and the reader.
Last edited by Ghrasp; August 7th, 2011 at 11:24 AM.
It is pretty well-established that Q, in thermodynamics, means "heat transfer"; or it can be just "heat".
Q is not a synonym for another word in you,re language.
I just mentioned that Q is mostly regarded as synonym for warmth in the Netherlands and wärme in Germany. Not that Q is synonym for warmth as my opinion.
Wärme
The link above shows and wärme is "pretty well established" for warmth in general terms of translating much more then heat.
But different then Dutch German language doesn,t really have a strong synonym for heat as a non verb as Dutch has with the word "hitte" and verb "verhitten") . It only has the verb form "Heizen" (to heat or verhitten in Dutch) but not heize as non-verb for heat or hitte. Heize is past tense for to heat : "heated" (or heating ?). Anyway it,s verb.
Verbs have past future and present to an event and hypothetical (as in : "I am going to heat the water for coffee") heat is future for me but present for the event. In past-tense : "The water is heated" Heated is past to me but present to the event.
Difference on the german wikipage for Q is made between wärmemenge (menge is quantaty) and wärme (both the symbol Q). That difference is more or less similar as between warming and warmth. A similar difference as between heat as verb and heat as non verb (for a latent, potential (or also used / to use potential ). Between heating (heizen) and warming heating relates more to "from a distance" and warming more to a fysical contact. That the distinction is not always sharp in practice is because both combine in a lot of situations. Someone using heating then pronounces the distance part (and with that the distance) more then the contact part.
If the distance part (radiation/electro-magnetic) is considered as heat [NM] it can not be calculated and counted as electromagnetic energy [Ws] witha total that would have Ws and/or Nm as units. That would be calculating from two approaches classic and modern the count up or subtract between the two approaches.
Some toughts that I would think are relevant related to the work of some known German fysics beit in original or translated.
Last edited by Ghrasp; August 8th, 2011 at 04:39 AM.
Look at your own post again and click the link- then click on the translation to English, the wiki page will go to the page for heat in thermodynamics. I really don't understand why you are arguing over different languages obviously having different words for the same concept. The symbol Q, in thermodynamics, represents heat transfer or just heat, heat transfer is a type of energy- as we can see here
it is not a energy per unit time as I think you have been saying (it's hard to understand with the language differences), that would be the quantity
For most steamengines this leaves out the dU for the coolingwater. It only covers the powerstroke part of a cycle to a generator. Warming coolwater can be considered part of the work for a steamengine (even if it,s often a loss but sometimes warm coolingwater can be used for another purpose making the loss to a gain). The cooling is water is used as an effective part of the engine in a way. Not just keeping the machine as a whole cool.Look at your own post again and click the link- then click on the translation to English, the wiki page will go to the page for heat in thermodynamics. I really don't understand why you are arguing over different languages obviously having different words for the same concept. The symbol Q, in thermodynamics, represents heat transfer or just heat, heat transfer is a type of energy- as we can see here
it is not a energy per unit time as I think you have been saying (it's hard to understand with the language differences), that would be the quantity
Cooling is necessary for the cycle to repeat and condense the water and maintain a frecquency for constant repeat. Then it is related to time because the working of the steamengine is. I suppose a cycletime T can be determined from the total volume of water and the flux for the watercurrent through the machine.
this can also be done for a cooling part of a fridge. If it contains two liter of fluid and the pump pumps two liter in 60 sec.
60 sec is T for a cycle. Then calculate dU for the total volume with T as repeattime gives energy to T or per second. From that a P can be calculated or at least estimated.
What exactly is your point? The equation dU = dQ - dW just shows the change in internal energy of a system due to the heat transfer to the system and the work done by the system on its' surroundings- are you actually trying to say that there is a flaw in this equation?
I put it confusing with "leaving out dU for the coolingwater" Dw would have been better there. Coolingwater is not just used for cooling. Steamturbines aren,t that hot to need that much coolingwater compared with a fuellengine. Coolingwater is working part of a turbine.
What certainly can,t be done with the equation is jumping from one system to the next combination for system as a combination of the first with an othersystem. That,s using a different system for parts of the ecquation. an amount of water is the technical system for all parts ; internalenergy allready tells.
For example dW is the energy by the water to the generator the system includes the generator as what the work is externalised to that,s not internal energy. Same equation dU and DQ is internal to the water the system is water.
dW water is not externalised to the generator with 100% rendition (and the fuell not to the fire and the fire not to the water).
It depends a lot on the mechanics for the generator what the rendition is for these steps.
dW water for using the equation is not "by the water to" or "to the water by". What does the work to the water or what the water does the work to is not relevant for the equation.
dW water as part of the change of internal energy can,t be skipped with two steps "to" and "from" jumping the water for dW and then subtract between to and from as when energy travels through a wall where the equation is for internal energy.
Last edited by Ghrasp; August 10th, 2011 at 04:18 AM.
Internal energy is the total energy contained within a thermodynamic system- it can be defined as the sum of all forms of energy intrinsic to the system , or written mathematically:
and it may also be defined as the vector sum of the molecular potential and kinetic energies of a system
Therefore, the change in internal energy of a system is
The key parameters of the change in internal energy are the heat flow Q and the mechanic work of the system, accordingly:
So, what problems have you with this, Ghrasp?
Stirring water in a pan you can,t add the stir of the water all as energy to an equation for internal energy. The kinetic energy of the water is not part of the internal energy or it would be counting the same phenomenon double for energy (or the water has no external kinetic energy). Only a minimum of the external kinetic energy (as the stir of the water) becomes internal energy. Otherwise every boat or fish would raise the waters temperature significant.
If we take all forms of energy out of sub-atomic particles, what's left?
Temperature is a greater perturbation of space, rather an increase in energy?
A little bit of matter is equivalent to a lot of energy - only if it goes into another region of space.
Is matter mostly space?
If I take a box of "nothing" from outside the Universe, and place it inside the Universe will matter or energy exist inside that box?
Do Neutron stars have a temperature? Is there space inside sub-atomic particles?
The kinetic energy of the molecules of water most certainly do contribute to the internal energy of the water- along with all other forms of energy which may affect internal energy; i.e. the potential energy of the water molecules. When you heat a given quantity of water, what happens? The water molecules will have an increase of kinetic energy (thus, increased velocity) due to the increase of temperature on the system- introducing "more energy" to the system; therefore, the internal energy of the water increases as temperature increases. When the water has a change of state to a gas (i.e. boiling), the potential energy of the water molecules will increase and so, again, increase the internal energy of the water.
Matter is the substance that gives a real entity, objective existence in space. Matter alone can form a physical object. Matter is real
Energy is the ability to do work. It is a qualification of a matter body and hence a functional entity. It has no real existence. It is the magnitude of stress formed about a matter body.
Time is a functional entity of duration compared with the interval required for a matter body, which is assumed to move at constant (linear) speed, to move through a definite distance in space.
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