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

Only horizontal velocity changes (in direction).
Initial horizontal velocity = - Final horizontal velocity = 15Cos45

Impulse = m × (Final velocity - Initial velocity)
= 2muCos45
= 2 × (20 × 10^-3 kg) × (15 m/s) × 1/√2
= 0.6 / √2
= 0.3√2 kgm/s

Impulse recieved by ball = 0.3√2 kgm/s