3 part speed and impulse question... give it a try!

Question

A 50 g ball of clay is thrown horizontally at 20 m/s toward a 1.7 kg block sitting at rest on a frictionless hi surface. The clayts and sticks to the block

What is the speed of the block and clay right after the collision?

What impulse does the clay exert on the block?

What impulse does the block exert on the clay?

All answers in two significant figures

Answer 1

a) The total impulse is conserved. At first, the impulse is:

p=mv=0.05*20=1 kgm/s

The total mass after the collision is 0.05+1.7=1.75 kg

The new speed is then v=p/m=1/1.75=0.57 m/s

b) The block has zero impulse before the collision. The new impulse is

p=mv=1.7*0.57= 0.97 kgm/s

c) The clay has 1 kgm/s impulse before the collision. Afterwards, it's 0.05*0.571=0.03 kgm/s