Question

A piston is slowly pushed into a metal cylinder containing an ideal gas. Which of the following statements is/are incorrect?

• A. The pressure of the gas increases
• B. The number of the molecules per unit volume increases
• C. The average speed of gas molecules increases
• D. The frequency of collision of the gas molecules with the piston increases

Answer 1

The correct option is C The average speed of gas molecules increases

When we slowly push the piston both temperature and pressure inside the cylinder will increased. Hence we can define it by $\text{Root mean square velocity}$ which is given as ${rms}_{velocity}=\sqrt{\frac{3RT}{m}}$ So not option $A$ is also correct but we have to focus on exact answer.