Question

A ball of mass 20g hits a wall at an angle of 45° with a velocity of 15m/s. If the ball rebounds at 90° to the direction of incidence, calculate the impulse recieved by the ball

Answer 1

v=15m/s

Impulse is given by  momentum change =m.Δv

=m.(vf−vi)sinθ

=0.02(−15−15)sin45∘

=0.42kg.m/s

Answer 2

Answer:

Let's consider the momentum vectors before & after hitting. 

As we know, 

Impulse=Change in momentum 

I=mv'-mv 

=(mvcos45+mvsin45)-(mvcos45-mvsin45) 

[since, vertical resolution cancel out and horizontal adds up] 

=2mvsin45 

=2*0.02*15*sin45 

=0.424 N-s

HOPE IT HELPS :)

Explanation: