Question

A ball of mass `0.5 kg` moving with a velocity of `2 m//s` strikes a wall normally and bounces back with the same speed . If the time of contact between the ball and the wall is 1 millisecond , the average force exerted by the wall on the ball is
A. `2000 N`
B. `1000 N`
C. `5000 N`
D. `125 N`

Answer 1

Correct Answer - A
`Delta p = 2 mv`
`F = (Delta p)/(Delta t) = (2 mv)/(Delta t) = ( 2xx 0.5 xx 2)/(10^(-3)) = 2000 N`