Why isn’t it sufficient to describe temperature as heat density?
In: Physics
The simple answer is that you have
stored heat = temperature * heat capacity
a load of water can contain a lot of “heat” at a low temperature, so that it’s really good for pulling heat out of hot objects, because the heat will keep flowing into the water until the *temperatures* balance, not the *amounts of heat ,* with the water ending up with much more of the heat to reach the same temperature.
It gets more complicated, usually we split heat capacity into
mass * specific heat capacity
So that we can talk about the heat given to a large or small amount of water. Then you could use the actual density of water and say:
stored heat/volume = temperature * specific heat capacity * mass/volume
or
heat density = temperature * specific heat capacity * mass density
So there is a connection between temperature and heat density in these situations, but it’s not them being the same thing.
But then things get even more complicated when you start to think about objects for which the relationship is not simple multiplication, because at different temperatures the specific heat capacity changes.
But that’s the basic thing.
Your title is pretty short, but, I think you’ve got it backwards. Heat, or, the amount of energy stored in temperature, is related both to the temperature itself and the amount of mass that is that temperature.
A 1 kg block of lead at 100K has twice as much heat as a .5kg block of lead at 100k.
Please reply if I’m really missing your point and I’ll try to answer your question.
Because dependent on material, different heat densities will manifest as different temperatures. Water holds a lot more heat per unit mass or volume than air or steel, and is therefore a different temperature when the same amount of heat is applied.
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