Question

A car of mass 1000 kg start from rest and moves 100 m in 2 seconds under the action of a constant force . The force acting on car is(in kN)
(1)100 (2)50 (3)20 (4)25​

Answer 1

SOLUTION

acceleration is....=a

100=0.5(a)2²

a=200/4=50m/s²

force.....

$= 1000 \times 50 = 50000n \\ = 50kn$

Answer 2

Explanation:

using second equation of motion

s = ut+ 1/2 a*t*t

here u = 0

s = 100 m

t = 2 sec

so

100 = 0*2+1/2* a *2*2

100 = 0+2a

a= 50 m/ s^2

now

F = m*a

m= 1000 kg

F = 1000*50 = 50000 N = 50000/1000= 50 KN