# There are two identical chambers, completely thermally insulated from surroundings. Both chambers have a partition wall dividing the chambers in two compartments. Compartment 1 is filled with an ideal gas and Compartment 3 is filled with a real gas. Compartments 2 and 4 are vacuum. A small hole (orifice) is made in the partition walls and the gases are allowed to expand in vacuum. Statement-1: No change in the temperature of the gas takes place when ideal gas expands in vacuum. However, the temperature of real gas goes down (cooling) when it expands in vacuum. Statement-2: The internal energy of an ideal gas is only kinetic. The internal energy of a real gas is kinetic as well as potential.

Question:

There are two identical chambers, completely thermally insulated from surroundings. Both chambers have a partition wall dividing the chambers in two compartments. Compartment 1 is filled with an ideal gas and Compartment 3 is filled with a real gas. Compartments 2 and 4 are vacuum. A small hole (orifice) is made in the partition walls and the gases are allowed to expand in vacuum.

Statement-1: No change in the temperature of the gas takes place when ideal gas expands in vacuum. However, the temperature of real gas goes down (cooling) when it expands in vacuum.

Statement-2: The internal energy of an ideal gas is only kinetic. The internal energy of a real gas is kinetic as well as potential.

1. Statement-1 is false and Statement-2 is true.

2. Statement-1 and Statement-2 both are true.

Statement- 2 is the correct explanation of Statement-1.

3. Statement-1 is true and Statement-2 is false.

4. Statement-1 and Statement-2 both are true.

Statement- 2 is not correct explanation of Statement- 1 .

JEE Main Previous Year Single Correct Question of JEE Main from Physics Kinetic Teory chapter.

JEE Main Previous Year Online April 9, 2013

Correct Option: 1

Solution:

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