Answer: 5/3.
- A 5/3
- B 7/5
- C exactly 1
- D 4/3
Correct answer: A. 5/3
Explanation: For a monatomic gas, γ = 5/3 ≈ 1.67.
Not all gas molecules move at the same speed - the Maxwell-Boltzmann distribution shows the spread, with the most probable speed vp slightly less than the average vavg, which is slightly less than the root-mean-square speed vrms used in the pressure formula.
Concept context
Kinetic theory of gases connects molecular motion to pressure and temperature, explaining gas laws, specific heats, and molecular speeds.