Question

A truck moving on horizontal road towards east with velocity 20m/s collides elastically with a light ball moving with velocity 25m/s along west.The velocity of ball just after collision

Answer 1

Answer:

65 m/s in East.

Explanation:

Explanation:Actually the given problem deals with a Truck of a very large mass M and a ball of very light mass m.

Since, the mass of the truck is much greater than that of the mass of ball. So, we get that M>>>m.

Letting the velocity after collision to be uy=-25 m/s(where it is in west direction).

And if we let the initial velocity of the truck to be ux=20 m/s.

So, on using conservation of momentum we will get that vx = (M-m)/(M + m)ux + (2M/ m + M)uy.

Since, we already took the mass of the ball as very less or negligible so on solving the equation with M we will get the vx = 65 m/s in the East direction.

For solving it you can assume the mass of ball m to be negligible, you will get 65 m/s East.