Physics · May / June 2017 · Paper 12 · Question 20

A fixed mass of gas is enclosed in a cylinder with a movable piston. The gas is initially at pressure $p_1$ and has a volume $V_1$. The temperature is kept constant. The piston is moved so that the pressure becomes $p_2$ and the volume becomes $V_2$. Which equation is correct?

1. A$\dfrac{p_1}{V_1} = \dfrac{p_2}{V_2}$
2. B$\dfrac{p_1}{p_2} = \dfrac{V_1}{V_2}$
3. C$p_1 V_1 = p_2 V_2$
4. D$p_1 V_2 = p_2 V_1$

As printed in the paper