A body of mass 0.5 kg travels in a straight line with velocity v =a x3/2 where a = 5 m–1/2 s–1. What is the work done by the net force during its displacement from x = 0 to x = 2 m?
Given,
Mass of the body, m = 0.5 kg
Velocity of the body is given by
v =a x3/2 where a = 5 m–1/2 s–1
At x = 0, initial velocity, u = 0
At x = 2, final velocity, v = 5 (2)3/2 = m s-1
According to work-energy theorem, work done is equal to the change in kinetic energy of the body.
Work done, W = ΔK
⇒ W = (1/2)mv2 – (1/2)mu2
⇒ W = (1/2) × 0.5 kg × ( m s-1)2 – (1/2) × 0.5 kg × 02
⇒ W = 50 J