Question

A horizontal cylinder has two sections of unequal cross-section in which two pistons $A$ and $B$ can move freely. The pistons are joined by a string. Some gas is trapped between the pistons. If this gas is heated, the pistons will

• A. move to the left
• B. move to the right
• C. remain stationary
• D. move either to the left or to the right

Answer 1

Answer: (B)

move to the right

The pressure of the gas remains constant, and is equal to the atmospheric pressure (for equilibrium of the `gas plus pistons' system). If the temperature of the gas is increased, its volume must increase. For this, the piston must move to the right