⚛️ Physics · Kinetic Theory · NEET & JEE

An ideal gas undergoes a process in which its pressure and volume are related by PV² = constant. Starting from an initial temperature T, if the volume of the gas doubles, the final temperature of the gas is:

Answer: T/2.

A 2T
B 4T
C T/2
D T

Correct answer: C. T/2

Explanation: From the ideal gas law, PV = nRT, and PV² = constant means P ∝ V⁻². Substituting, T = PV/(nR) ∝ V⁻¹, so doubling V halves T, giving a final temperature of T/2.

Not all gas molecules move at the same speed - the Maxwell-Boltzmann distribution shows the spread, with the most probable speed v_p slightly less than the average v_avg, which is slightly less than the root-mean-square speed v_rms 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.

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An ideal gas undergoes a process in which its pressure and volume are related by PV² = constant. Starting from an initial temperature T, if the volume of the gas doubles, the final temperature of the gas is:

Concept context

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