Question

The internal energy of an ideal gas decreases by the same amount as the work done by the system.

• A. The process must be adiabatic.
• B. The process must be isobaric.
• C. The temperature must decrease.
• D. The process must be isothermal.

Answer 1

Answer: (A), (C)

The temperature must decrease.
The process must be adiabatic.

The internal energy of an ideal gas decreases by the same amount as the work done by the system.

Change in internal energy=work done+heat exchange

change in internal energy=work done if process has no heat exchange, i.e. it's adiabatic and the temperature must decrease