Question

A ball of mass 1 kg initially moving with a velocity of 10m /s goes and collides with the wall and returns back along the same line with the velocity of 8m/s.Then the change in momentum of the ball is *
a) 2kg m/s
b) 18kg m/s
c) 20 kg m/s
d) 30 kg m/s

Answer 1

Explanation:

Initial velocity u=10m/s and final velocity v=0(rest)

so the change in momentum will be ΔP=mΔV=m(v−u)=1kg(0−10)=−10Kgm/s

So magnitude of the impulse will be 10Kgm/s

Answer 2

18kgm/s is the answer steps in the pic