Question

120 N
A car is moving with a uniform velocity of 30 ms!
It is stopped in 2 s by applying a force of 1500 N
through its brakes. Calculate : (a) the change in
momentum of car, (b) the retardation produced in
car, and (c) the mass of the car.
Ans. (a) 3000 kg m s-1 (b) 15 m s-2 (c) 100 ko​

Answer 1

Explanation:

u=30 ( u is initial velocity)

v=0 ( v is final velocity)

t=2s ( time)

Answer 2

Explanation:

a) F=ΔP/t

ΔP=F×t

ΔP=1500×2=3000kgm/s

b) retardation is the decrease in acceleration so

a=v/t

a=30/2

a=15m/s²

c) F=ma

m=F/a

m=1500/15

m=100kg