Thermodynamics

JEE Main level, single correct, medium

25 of 190

Question 25 of 190

Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : In an insulated container, a gas is adiabatically shrunk to half of its initial volume. The temperature of the gas decreases.

Reason (R): Free expansion of an ideal gas is an irreversible and an adiabatic process.

In the light of the above statements, choose the correct answer from the options given below :

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Answer: (B) (A) is false but (R) is true

If the container is insulated then temperature is expected to increase in adiabatic compression. So (A) is wrong.
And free expansion is irreversible and adiabatic process. So (R) is correct.

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