Question

In the figure shown, n molecules of a gas of mass nm move only along x-axis (i.e. either towards +ve x-axis or –ve x-axis) inside a cube of edge 1m. Half molecules have speed v and other half have 2v. The pressure on a wall ^ to x-axis is –

• A. 2.5 n m v²
• B. $\frac{nmv^{2}}{5}$
• C. $\frac{3}{2}$ n m v²
• D. None

Answer 1

Answer: (A)

2.5 n m v²

Answer 2

Pressure = (momentum transferred to wall in one second)/Area of wall