MCQ
When a gas expands adiabatically
- ANo energy is required for expansion
- BEnergy is required and it comes from the wall of the container of the gas
- ✓Internal energy of the gas is used in doing work
- DLaw of conservation of energy does not hold
✓
Answer
Correct option: C.
Internal energy of the gas is used in doing work
(c) $\Delta Q=\Delta U+\Delta W=0 \Rightarrow \Delta W=-\Delta U$if $\Delta W$ is positive i.e., gas does work then $\Delta U$ should be negative meaning internal energy is used in doing work.
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