Which one of the following conditions would always result in an increase in the internal energy of a system?
A)The system loses heat and does work on the surroundings.
B)The system gains heat and does work on the surroundings.
C)The system loses heat and has work done on it by the surroundings.
D)The system gains heat and has work done on it by the surroundings.
E)None of the above is correct.

Question

Quizplus · Accepted Answer

According to the First Law of Thermodynamics, the change in internal energy (ΔU) of a system is equal to the heat added to the system (Q) minus the work done by the system (W): ΔU = Q - W. If the system gains heat (Q > 0) and has work done on it by the surroundings (W < 0), then the internal energy of the system will increase (ΔU > 0). Therefore, choice D is the correct answer.

Which One of the Following Conditions Would Always Result in an Increase