Question

When 40 J of heat is absorbed by a monatomic gas, the increase in the internal energy of the gas is

• A. 12 J
• B. 16 J
• C. 24 J
• D. 32 J

Hint:

For monatomic gases, internal energy change is given by \( \frac{3}{5} Q \) in an isothermal process.

Answer 1

The Correct Option is C

For a monatomic gas, the first law of thermodynamics states: \[ \Delta U = \frac{3}{5} Q \] Given: \[ Q = 40 J \] \[ \Delta U = \frac{3}{5} \times 40 \] \[ = 24 J \] Thus, the increase in internal energy is 24 J.