A `0.5 kg` ball moving with a speed of `12 m//s` strikes a hard wall at an angle of `30^(@)` with the wall. It is reflected with the same speed and at the same angle . If the ball is in contact with the wall for `0.25 s`, the average force acting on the wall is

Options

A. `96N`
B. `48N`
C. `24N`
D. `12N`

Answer

c

Explanation

Here, `m = 0.5kg, upsilon = 12m//s, theta = 30^(@)`
`t = 0.25 s, F = ?`
As Impulse = change in linear momentum
`:. F xx t = 2 m upsilon sin 30^(@)` (perpendicular to the wall)
`F = (2m upsilon sin 30^(@))/(t) = (2xx0.5 xx12)/(0.25) xx (1)/(2) = 24N` .