Answer: 7/5.
- A 7/5
- B 5/3
- C exactly 1
- D 3/2
Correct answer: A. 7/5
Explanation: For a diatomic gas, γ = 7/5 = 1.4.
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.