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Len33

Hot, or cold?

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For the 'Chat about anything here' pages, I have something for you to think about and it has absolutely nothing to do with time-pieces.

Take two equal amounts of water, the amount not being in any way important.

For example, let's say "one pint."

Now, one pint is at fresh boiling point and the other pint is at cold (Tap) temperature.

(Exact temperatures of each, totally unimportant)

Pour the two amounts into any container.

Right, what I would like to know is this:-

Does the boling water become cooler, or does the cold water become warmer?

Not a trick question and not a joke. 

I would be very interested to see what anyone has to say and why.

Thanks.

 

 

 

 

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Heat " IS"  the kenetic energy of constituant particles. If water molecules are moving, there is heat. If at rest , no heat. 

What we call / preceive  as the heat in content in the boiling water is the amount of kenetic energy of water molecules (sum of all molecules in it)  as molecules vibrate about.

Temperature is the amplitute of vibration, the larger the amplitude the higher thermometer show the temp.

So as you mix the cold and hot,  molecules vibrating at higher amplitude beat on the ones with low amplitude( cold ones) in doing so some kenetic energy ( heat) is transfered from high temp to low temp molecules. ( like when billiard balls collide), this will continue until no excess kenetic energy ( heat is there to be transfered) the estate which is reffered to as equilibrium.

Furthure you can understand that,  there is no such thing as cold energy, cool is just a lack of heat or lower heat content.

 

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2 hours ago, Nucejoe said:

TexasDon,  I wouldn,t dream of telling but the truth to longhorns.:lol: 

As a sooners neither would I want to bid on longhorns homecomings. No Sir. 

Regards 

I meant longhorns homegames. Big eight they were in my days.

 

 

 

 

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Hi Andy,  The link introduces/defines Thermodynamic which is the study of heat energy conversion to work and vice versa. It is about transformation of energy. One form of energy (heat) transforming into another form ( work) and not concerned with transfer of heat, from hot to cold.

Understanding the nature of heat and the mechanism heat transfers from hot source to cold, is a key len33 is prepared to use. His question shows him ready to absorb the concept.

Regards joe

 

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7 hours ago, Nucejoe said:

Hi Andy,  The link introduces/defines Thermodynamic which is the study of heat energy conversion to work and vice versa. It is about transformation of energy. One form of energy (heat) transforming into another form ( work) and not concerned with transfer of heat, from hot to cold.

Understanding the nature of heat and the mechanism heat transfers from hot source to cold, is a key len33 is prepared to use. His question shows him ready to absorb the concept.

Regards joe

 

 

Indeed. However the link I gave describes the fundamental concepts of thermodynamics and in the process introduces the concept we are trying to describe. The page links on to the concepts of heat transfer, but (arguably), you need to understand the fundamental ideas first, before you can accept the ideas relating to heat transfer.

In this case we are dealing with heat transfer, and the second law of thermodynamics.
https://en.wikipedia.org/wiki/Heat_transfer

More specifically the concept that ... "When an object is at a different temperature from another body or its surroundings, heat flows so that the body and the surroundings reach the same temperature, at which point they are in thermal equilibrium."

You can either consider the hot water entering the cold as a single body, or as many smaller bodies (the water molecules), either way, the net result is the same. The hot body gets colder (looses energy), and the cold body gets hotter (gains energy) until the system reaches thermal equilibrium.

These laws deal with idealised cases, where no heat is lost to the surroundings. In the real world, of course some energy is lost, as the hot and cold water mix heats up the room and attempts to bring it too in to thermal equilibrium.

 

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Surely you agree, learners get baffled as soon as the next topic comes up.

Namely " entropy " as though the subject is above their head.

It is not, one can understand entropy like any other concept,  if they understand heat before going on to next step . So I try to emphesize that the hot body is not "getting" cold, it is not getting anything in any sense of the word virtual or actual.. RATHER hot body is loosing heat and not getting cold  and that heat fllow is one directional. Heat flows from Hot to less hot or to cold. ....Period. There is nothing to flow in the opposit direction whatsoever. Nothing to be got.

Once the learner gets this he is ready to understand the one directionality of entropy. And the isentropic process. 

Len33 says no trick question no joke. To me that means he wants to know, he thought of the question himself and have thought about it enough to be ready to absorb with high efficiency, so I should  go to greate length to make sure he dose not leave us with any grade  less A++++.  Which he deserves.

Thank you for the discusion. 

 

 

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There is a PhD at the very least, and perhaps a Nobel prize for anyone who can invent an entropy containment field I can place around my work area to prevent parts randomly vanishing, only to then randomly re-appear many hours or days later (or perhaps never, in some cases). :D

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