A constant force acts on a body of mass 0.9 kg at rest for 10 s . If the body moves a distance of 250 m, the magnitude of the force is

Options

A. 3N
B. 3.5N
C. 4.0N
D. 4.5N

Answer

D

Explanation

` u = 0,S = 250m,t = 10 sec`
`S = ut + (1)/(2) at^(2) rArr 250 = (1)/(2)a(10)^(2) rArr a = 5 m//s^(2)`
So,F = ma = 0.9 xx 5 = 4.5 N`