Question

A ball of mass 'm' is projected from the ground with a speed 'u' at an angle 'a' with the
horizontal. The magnitude of the change in momentum of the ball over a time interval from
beginning till it strikes the ground again is​

Answer 1

Explanation:

Over the course of the journey, the velocity of the ball in the x-direction is constant. So the momentum in that direction remains the same.

Initial momentum in y-direction p

yi

=musinα

Final momentum in y-direction p

yf

=−musinα

∴ change in momentum =−2musinα

Magnitude of change =2musinα