Heat of a solid under high pressure

[dBrandon/dC]

I was wondering - when pressure is applied to solids, do they heat up? Not pressure like an impact - I'm not talking about conversion of kinetic energy. But suppose a piece of iron is put in a hydraulic press and the pressure increases slowly. More specifically, I'm wondering about the rocks deep inside the earth. Do solids generate heat simply by being under pressure? It seems like high pressure could restrict the thermal motions of the molecules, causing them to generate heat simply by their vibrations. But since solids are generally incompressible, I didn't know if this would happen. I'm posting this here because I thought the answer may be more related to Q/M than to classical physics.

 

[Bill_K]

When you compress a solid or any other object, you do mechanical work, which is converted to heat, raising the object's temperature. This only happens during the compression process. Afterwards if you give it a chance, the heat will dissipate and the object will cool off to the temperature of its surroundings. It does not stay hot simply by virtue of being in a compressed state.

Why is the Earth's core hot? That's a different question entirely. Some of the heat comes from radioactivity, although it's not universally agreed how much of a contribution this makes.