Question

A car is moving with a uniform velocity of 30m/s. It is stopped in 2 s by appling brakes. Calculate : (a) the change in momentum of the car (b) the retardation produced in car (c) the mass of the car.

Answer 1

I will try my best to answer this question.

U= - 30m/s
V=0
t=2s
F=1500N (to stop the car)
V=u+at
0=30+2a
=a = - 15m/s² (Retardation)
F=ma
M=f/a =1500/15 =100kg
Pf-pi=m(v-u)
100(0-30)
=-300kgm/s²