Question

If you

have a system which you put 400 J of heat into and it does 250 J of
work; what happens to the internal energy?

Answer 1

When 400 J of heat is added to a system and it does 250 J of work, the internal energy of the system increases by 150 J according to the first law of thermodynamics.

Step-by-step explanation:

To determine what happens to the internal energy of a system when heat is added and work is done, we can use the first law of thermodynamics. This law is given by the formula ΔU = Q - W, where ΔU is the change in internal energy, Q is the heat added to the system, and W is the work done by the system.

In this case, the student puts 400 J of heat into the system (Q = +400 J) and the system does 250 J of work (W = 250 J). As per the first law of thermodynamics, the change in internal energy (ΔU) would be calculated as follows:

ΔU = Q - W

ΔU = 400 J - 250 J

ΔU = 150 J

Therefore, the internal energy of the system increases by 150 J.