[alancalverd]

No, my friend. Let's go back to the stressed spring. Take two identical springs, compress one of them, let their temperatures equilibrate to ambient, and place them in contact. One clearly has more internal energy than the other but there is no heat transmission between them.

[hamdani yusuf (OP)]

And when we look at heat transfer between objects, we recognise that there is none between bodies at the same temperature, from which we infer that temperature is a measure of the mean internal kinetic energy of a body.

I can accept this. But can you be more specific about the definition of "internal" here?

So, what's your answer to this question : what is temperature?

A measure of the internal kinetic energy of a body.

You need to specify what you mean with internal and kinetic, in contrast to external and potential.

[alancalverd]

Imagine a bullet fired from a high-flying aircraft. Ignoring the residual heat from the propellant and barrel friction, it leaves at ambient temperature, say -20C, which is a measure of its internal kinetic energy. It initially travels at 500 m/s, which defines its external kinetic energy. En route it is slowed by air friction, some of which results in heating, thus depleting the external and increasing the internal k.e.

Kinetic: associated with movement.

[Spring Theory]

Something missing in the above.
[h] = ML²T^-1

[c] = LT^-1


so you can't set both c and h  to a dimensionless unity simultaneously.

You have never taken a theoretical physics class.  They work in natural units.

Here are some good vids you can get educated on natural units:

Sabine Hossenfelder -

Curt Jaimungal -

[Spring Theory]

I bend over backwards here trying to help you guys understand concepts and be productive to the topic but the typical response is just an unproductive, smart ass quip.

What a waste of time and effort. You guys deserve neither.

Since most of what you bring to the party is pseudoscience, leaving the discussion is no loss.

I guess that means Leonard Susskind is teaching pseudoscience courses at Stanford University.

[hamdani yusuf (OP)]

Imagine a bullet fired from a high-flying aircraft. Ignoring the residual heat from the propellant and barrel friction, it leaves at ambient temperature, say -20C, which is a measure of its internal kinetic energy. It initially travels at 500 m/s, which defines its external kinetic energy. En route it is slowed by air friction, some of which results in heating, thus depleting the external and increasing the internal k.e.

Kinetic: associated with movement.

Ok. If the bullet also spins, it should also be an external energy, right?

[alancalverd]

Yes, spin energy is also external kinetic energy.

[alancalverd]

Here are some good vids you can get educated on natural units:

You might do well to study them yourself and see where your assertion of 29 May is incorrect.

[hamdani yusuf (OP)]

Here's a real life example. A reactor requires a right amount of cooling for normal process. Too much cooling, the temperature is too low and reaction won't start. Inadequate cooling causes runaway reaction and the product boils. The temperature is controlled by flow of cooling water to reactor jacket.
At higher flow, the cooling water has higher kinetic energy. But the temperature is almost the same. Thus the water flow here is considered as external kinetic energy.
The question is, how do the water molecules and reactor wall know the difference between internal and external energy?

[alancalverd]

"know"? Chemical engineers are is clever and know a lot, chemicals are dumb and know nothing.

Do not confuse "almost" with "equals".

And if the cooling water does not leave at a higher temperature than it arrives, it is not cooling anything - check both gauges!

Anyway, the answer is "temperature".

[hamdani yusuf (OP)]

Here's an interesting experiment related to this thread.

Cooling curves - stearic acid cooling from a liquid to a solid
Changes in state cause bonds to be broken or made. It takes energy to break bonds, and making bonds releases energy.

[hamdani yusuf (OP)]

Cooling Gases

Universal technique for condensing common gases and studying their liquid phases. Have you seen blue oxygen?

This video is part of the Flinn Scientific Best Practices for Teaching Chemistry Video Series, a collection of over 125 hours of free professional development training for chemistry teachers - http://elearning.flinnsci.com

ATTENTION: This demonstration is intended for and should only be performed by certified science instructors in a safe laboratory/classroom setting.

[hamdani yusuf (OP)]

"know"? Chemical engineers are is clever and know a lot, chemicals are dumb and know nothing.

Do not confuse "almost" with "equals".

And if the cooling water does not leave at a higher temperature than it arrives, it is not cooling anything - check both gauges!

Anyway, the answer is "temperature".

The reactor wall seems to be able to "distinguish" between internal and external kinetic energy in the cooling water. What's our best model to distinguish them?
As far as possible, I try to avoid circular reasoning. Like saying that temperature is internal kinetic energy, and continues explaining that internal kinetic energy is temperature.

[Bored chemist]

Here's an interesting experiment related to this thread.

Cooling curves - stearic acid cooling from a liquid to a solid
Changes in state cause bonds to be broken or made. It takes energy to break bonds, and making bonds releases energy.

Did you imagine that we are not aware of that sort of behaviour?

[Bored chemist]

ATTENTION: This demonstration is intended for and should only be performed by certified science instructors in a safe laboratory/classroom setting.

Do you understand that I have done those sorts of experiments?

[alancalverd]

The reactor wall seems to be able to "distinguish" between internal and external kinetic energy in the cooling water. What's our best model to distinguish them?
As far as possible, I try to avoid circular reasoning. Like saying that temperature is internal kinetic energy, and continues explaining that internal kinetic energy is temperature.

Temperature is a measure of internal kinetic energy.
Beware of using anthropic terms like "distinguish" - you will confuse yourself.
If a body A has more of anything than body B, which way will "anything" flow? (NB there are a couple of  significant contradictions to the obvious answer).

[hamdani yusuf (OP)]

Did you imagine that we are not aware of that sort of behaviour?

If you don't think that it is interesting, you can just ignore it.

One thing that could be interesting to discus is why heating curve has different shape than cooling curve, among others.

[hamdani yusuf (OP)]

ATTENTION: This demonstration is intended for and should only be performed by certified science instructors in a safe laboratory/classroom setting.

Do you understand that I have done those sorts of experiments?

So what?

[hamdani yusuf (OP)]

The reactor wall seems to be able to "distinguish" between internal and external kinetic energy in the cooling water. What's our best model to distinguish them?
As far as possible, I try to avoid circular reasoning. Like saying that temperature is internal kinetic energy, and continues explaining that internal kinetic energy is temperature.

Temperature is a measure of internal kinetic energy.
Beware of using anthropic terms like "distinguish" - you will confuse yourself.
If a body A has more of anything than body B, which way will "anything" flow? (NB there are a couple of  significant contradictions to the obvious answer).

Let me simplify the case.
At the beginning, reactor wall and cooling water has the same temperature, say 30°C. The water doesn't flow, all of its kinetic energy is internal type. No heat transfer occurs.
Then with some method, the water is made to flow while keeping its total kinetic energy. Some of its internal kinetic energy is converted to external kinetic energy. This makes the water temperature to drop. Let's say we can manage to reduce the temperature to 25°C.
The last action produces temperature difference between reactor wall and cooling water, which causes heat transfer from reactor to water. Why it reacts differently even though the water has the same total kinetic energy? What's the distinguishing characteristics of internal kinetic energy that makes it different than external kinetic energy?

[hamdani yusuf (OP)]

If a body A has more of anything than body B, which way will "anything" flow? (NB there are a couple of  significant contradictions to the obvious answer).

Which way will they go?