FRQ — Thermodynamics

Short answer·Standard multi-step (3/5)·No calculator

Difficulty guide

The label describes the problem, not your ability.

1/5 - Foundational

Warm-up setup; checks one basic idea.

2/5 - Routine exam skill

Normal syllabus skill; usually one main rule or interpretation.

3/5 - Standard multi-step

Exam-style problem with multiple steps or a common trap.

4/5 - Hard exam skill

High-end exam problem; combines methods carefully.

5/5 - Challenge

Stretch problem beyond normal exam pressure.

Question

During compression,

120\text{ J}

of work is done on a gas and the gas loses

50\text{ J}

of heat to the surroundings.

Total: 3 marks

(a) Write $Q$ and $W$ where $W$ is work done by the gas. (1 mark)

(b) Find $\Delta U$ . (2 marks)

Your response (optional — you can also work on paper)

Something wrong with this item?