Saved Bookmarks
| 1. |
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 |
|
Answer» per second are thrown on the wall at right angles to it.mass = minitial velocity = - u before HITTING the wall, towards the wallfinal velocity = u after hitting the wall and rebounding, away from the wallChange 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. |
|