Question

The velocity of a body of mass 10kg increases from 4m/s to 8m/s when a force acts on it for 2s.What is the momentum before the force acts.

Answer 1

Explanation:

m = 10 kg

initial velocity = 4m/s

final velocity = 8 m/s

time = 2s

force = ma

= m × v-u/t

= 10 × 8 -4 /2

= 10 x 2

= 20 N

initial momentum p = mu

= 10 × 4

= 40 kg m/s

final momentum p = mv

= 10 × 8

= 80 kg m/s