Question

What is the change in internal energy if 20 J of heat is released from a system and the system does 50 J of work on the surroundings?

A.-80 J
B.-20 J
C.80 J
D.20 J

Answer 1

C. 80 J

Step-by-step explanation:

dU = dq + w

dU = -20 J + (-60 J) = -80 J