Question

A car of 1000 kg moves with a velocity of 10m/s.On applying brakes it comes to rest in 5 s.Then what are its initial momentum and final momentum? ​

Answer 1

Answer:

Given : m=1000 kg u=10 m/s t=10 s

Applied force F=1000 N (forwards)

Retarding force f=500 N (backwards)

Acceleration of the car in forward direction a=

m

F−f

=

1000

1000−500

=0.5 m/s

2

Using v=u+at

∴ v=10+0.5×10=15 m/s

Answer 2

Answer :-

m = 1000 kg

u = 10 m/s

v = 0

t = 5s

Initial momentum = mu

= 1000 × 10 =10000 kg m/s

Final momentum = mV

= 1000 × 0 = 0 Kg m/s