# A bowling machine is throwing tennis balls of mass m and velocity u each towards a wall . the balls hits the wall at 90 degree and rebounds with same velocity. the machine throws n balls per second. the force on the wall is

1
by chimanlal1172

2015-04-24T13:44:43+05:30

### This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
N balls per second are thrown on the wall at right angles to it.
mass = m
initial velocity = - u  before hitting the wall, towards the wall
final velocity =  u after hitting the wall and rebounding, away from the wall
Change of momentum of the ball during collision = m u - (-m u)  = 2 m u

As n balls are hitting the wall in 1 sec,  the total change of momentum of all the balls together in one second  =  2 n m u

Force = change of momentum per second.

Force exerted by the wall on all the balls = 2 n m u

Hence the force experienced by the wall = 2 n m u, as action and reaction forces are equal and opposite in direction.

click on the Thanks button (Azure blue color) above pls