Question

A car of mass 1,000 kg is moving at a speed of
20 ms-1
It is brought to rest at a distance of 50 m.
Calculate the net force acting on the car.
4,000 N
3,000 N
2,000 N
1,000 N​

Answer 1

Explanation:

mass = 1000 kg

u = 20 m/s

v = 0 m/s

s = 50 m

using third equation of motion

v² = u²+2as

0² = 20²+2×a×50

-400 = 100a

a = -4 m/s²

F = ma

= -4 × 1000

= -4000

hence force acting = 4,000 N ( in opposite directions)