Question

Find the distance through which a body moves when a constant force of 10 N acts on it to change it’s kinetic energy from 20 J to 40 J.

Answer 1

Let the distance covered by body is x.

constant force applied on body, F = 10N

initial kinetic energy = 20J

final kinetic energy = 40J

so, change in kinetic energy = Workdone on body

or final kinetic energy - initial kinetic energy = force applied on body × distance covered by body

or, 40J - 20J = 10 × x

or, 20 = 10x

or, x = 2 m

here, distance covered by body is 2m