A nozzle throws a stream of gas against a wall with a velocity v much larger than the thermal agitation of the molecules. After collision of the molecules with wall the magnitude of their velocity remains same. Also assume that the force exerted on the wall by the molecule is perpendicular to wall. (This is not strictly true for a rough wall.) Find the pressure exerted on the wall. (n = number of molecules per unit volume, m = mass of a gas molecule)

Options

A. `2n m v^(2)cos^(2)theta`
B. `3n m v^(2)cos^(2)theta`
C. `n m v^(2)cos^(2)theta`
D. `2n m v^(2)sin^(2)theta`

Answer

A