10,000 small balls, each weighing 1 gm , strike one square cm of area per second with a velocity 100 m/s in a normal direction and rebound with the same velocity. The value of pressure on the surface will be

Options

A. `2xx10^(3)Nm^(-2)`
B. `2xx10^(5)Nm^(-2)`
C. `10^(7)Nm^(-2)`
D. `2xx10^(7)Nm^(-2)`

Answer

D

Explanation

Pressure,
`P=(F)/(A)=(n[mv-(-mv)])/(A)=(2mnv)/(A)`
`=(2xx10^(-3)xx10^(4)xx10^(2))/(10^(-4))`
`=2xx10^(7)Nm^(-2)`