Question

A ball of mass 20g hits a wall at an angle 45 with velocity of 15m/s.if ball rebounds at 90 to direction of incidence,calculate impluse received by ball​

Answer 1

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

All the best!!