Question

A car is moving with uniform velocity 30m/s it stopped in 2sec by applying a force of 1500N through it's break find change in momentum of car

Answer 1

GIVEN~ u = 30m/s

v = 0

t = 2 sec

F = 1500N

TO FIND~ mv - mu = ? , m = ? , a = ?

SOLUTION~ As we know ~ a = v - u/t

therefore a = v - u/t

a = 0 - 30/2

a = 30/2

a = 15 ms^2

NOW,

F = m × a

1500 = m × 15

1500/15 = m

m = 100 kg

NOW,

mv - mu = ?

mv - mu = 100 × 0 - 100 × 30

mv - mu = 0 - 3000

mv - mu = -3000kg.m/s