Question

A body of mass 10 kg is moving with velocity 10m/s a force of
20 N is applied for 30s What is the change in momentum of the
body?
(a) 300 kg.m/s, (b) 600 kg.m/s,
(c) 400 kg.m/s, (d) 450 kg.m/s.

Answer 1

Answer:

Given , Mass of object, m=10 kg

Velocity of object, v=20ms

−1

Initial Kinetic energy, K

1

=

2

1

×10×20

2

=2000 J

Now, Final mass, m

2

=20 kg

Final Velocity, v

2

=10m/s

Final Kinetic energy, K

2

=

2

1

×20×10

2

=1000 J

Required Ratio =

K

2

K

1

=

1000

2000

=2:1

Explanation: