Question

a car starting from rest attains a velocity of 72 km per hour in 20 seconds find the force exerted on the car if its mass is 100 kg also find initial Momentum and final momentum

Answer 1

F=100 N
initial momentum=0
final momentum=2000 kgm/s

Answer 2

as car is starting from rest
u=0
v=72 km/h
we have to convert it into m/s
=72x1000/3600
=20m/s = v
a=v-u/t
f=ma
=m(v-u/t)
=100(20/20)
f=100N
initial momentum = mu = 100x0 = 0 kgm/s
final momentum = MV = 100*20 = 2000 kgm/s