Question

What is the amount of heat transferred when the internal energy of a thermodynamic system increases by 300 joules, and 75 joules of expansion work are done?

a) 375 joules
b) 225 joules
c) 425 joules
d) 300 joules

Answer 1

The amount of heat transferred when the internal energy of a system increases by 300 joules and 75 joules of expansion work are done is 375 joules, according to the first law of thermodynamics. Hence, the correct answer is option (a).

Step-by-step explanation:

The question relates to the first law of thermodynamics, which is a principle of energy conservation. This law states that the change in internal energy of a system (ΔU) is equal to the amount of heat transfer (Q) to the system minus the work done (W) by the system. The formula can be written as ΔU = Q - W.

In the given problem, the internal energy of the system increases by 300 joules and the system does 75 joules of work.

Therefore, using the formula ΔU = Q - W, the amount of heat transferred (Q) to the system can be calculated as Q = ΔU + W = 300 J + 75 J = 375 J.

Therefore, the correct answer is a) 375 joules.