JEE Main202331 Jan 2023Evening ShiftPhysicsThermodynamicsActual
Heat energy of 735 J is given to a diatomic gas allowing the gas to expand at constant pressure. Each gas molecule rotates around an internal axis but do not oscillate. The increase in the internal energy of the gas will be:
Options
- A525   J
- B441   J
- C572   J
- D735   J
Correct answer
A. 525   J
Step-by-step solution
For isobaric process and diatomic gas we can write, Δ Q = n C P Δ T = 735   J ⇒   n 7 R 2 Δ T = 735   J ⇒ n R Δ T = 210 Now internal energy will be, Δ U = n C V Δ T = n 5 R 2 Δ T = 5 2 × 210 = 525   J