Question 4B.5

[Jonathan Sautter 1J]

The question asks:
The internal energy of a system increased by 982 J when it was supplied with 492 J of energy as heat. (a) Was work done by or on the system? (b) How much work was done?

For part a) I got that work will be done on the system, but for part b) I got that w= 490J since deltaU= q + w. Since deltaU=982, you get the equation 982=492 + w. With this equation I just solved for w to get my answer. However, the textbook says the answer is 900J. Could someone explain what I am doing wrong or is the textbook wrong?

[Quade Albert 2J]

a. Work was done on the system

b. w = 982 J
q = 492 J
w = ΔU-q
w = 982 J - 492 J = 490 J

This is what I got I'm not sure how the textbook got 900 J.

[Allison Peng 1D]

Pretty sure you're correct, I got the same thing.