What is negative heat capacity ?

[magnetar]

Main Question or Discussion Point

what is" negative heat capacity"?

what is "negative heat capacity"? what is the example of it?

 

[Matterwave]

I can't imagine there would be such a case! For a negative heat capacity would imply that as you put more energy into a system, the system gets colder. Or as you take energy away from a system the system gets hotter. Both of these scenarios violate conservation of energy. AFAIK.

But, I haven't studied all of physics, so correct me if I'm wrong...

 

[nicksauce]

1) Negative heat capacity is simply when as you put energy into a system, its temperature decreases
2) One example is a black hole... I cannot think of any others.

 

[nealh149]

i believe there are certain paramagnetic systems that have negative heat capacity (with constant pressure) at low temperatures.

 

[Vanadium 50]

Any gravitationally bound system will have negative heat capacity - it doesn't have to be a black hole.

 

[Mapes]

i believe there are certain paramagnetic systems that have negative heat capacity (with constant pressure) at low temperatures.

Can you give a reference for this? I thought gravitationally bound systems were the only example, and would like to learn more.