A gas absorbs 800 J of heat and does 300 J of work on its surroundings. What is the change in its internal energy?
Answer and explanation
Correct answer: C. 500 J
- Step 1: First law: with the work done by the gas.
- Step 2: J.
Answer
500 J.
Why not the others: 1100 J: the work is added instead of subtracted. -500 J: the sign of the result is reversed. 800 J: the work done is ignored.
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