# Heat physics question

1. Jun 26, 2006

### touqra

If two objects of different kind is placed together, they have the same temperature. Would the amount of energy in the two objects the same too?

2. Jun 26, 2006

### Danger

It's possible, but not likely. There are all sorts of energy that each can possess independent of the other. If they're of exactly the same mass, then their thermal energy will be the same.

3. Jun 26, 2006

### Cyrus

The internal energy of an object can be approximated by:

$$U = m C_v T$$

That should give you an answer.

4. Jun 26, 2006

### Staff: Mentor

Trick question: temperature is a measure of energy (if we're just talking kinetic).

5. Jun 26, 2006

### Danger

But that's an if that wasn't specified. Hence the ambiguity of my answer. If, for instance, one was more massive than the other, it's potential energy would be higher. On the lowest level, e=mc^2 applies to both, so the mass is the determining factor.

6. Jun 27, 2006

### Cyrus

Actually, potential energy is defined as P.E = mgh

Where the height, h, is referenced to any arbitrary datum. So if you define the ground as your datum, then anything at ground level will have zero potential energy, no matter the mass.

Another example, an object below ground level (using ground level as the datum) would have negative potential energy.

So there are two ways a heavier body can have less potential energy than a lighter body.

If both bodies are above the datum or below, then your statement always holds true.

7. Jun 27, 2006

### Danger

True; I oversimplified as well. The point, though, was just to explain that the question isn't answerable in its current phraseology. More information is required.