Answer:
5.22 Ns
Explanation:
A consequence of Newton's second law of motion is that:
Impulse = change in momentum
The initial momentum = (0.145 kg) × (15.0 m/s)
The final momentum = (0.145 kg) × (-21.0 m/s)
The final momentum has a negative sign because the ball returned in an opposite direction.
Change in momentum = final momentum - initial momentum = (0.145 kg) × (-21.0 m/s) - (0.145 kg) × (15.0 m/s)
= -0.145(21.0 + 15.0) kg m/s
= -0.145 × 36.0 kg m/s
= -5.22 kg m/s
The magnitude of the impulse is thus 5.22 Ns.
