A body of mass 5 kg is moving with a momentum of 10 kg m/s. A force of 0.2 N acts on it in the direction of motion of the body for 10 s. The increase in it's kinetic energy is:

Explanation

The initial momentum of the body is given as 10 kg m/s. Using the definition of momentum, we can find the initial velocity of the body as:p = mv10 = 5vv = 2 m/sThe force acting on the body is 0.2 N and it acts for a duration of 10 seconds. Therefore, the work done by the force is:W = Fd = (0.2 N)(2 m/s)(10 s) = 4 JThe change in kinetic energy of the body is equal to the work done by the force:ΔK = W = 4 JThe final kinetic energy of the body can be calculated using the formula:Kf = (1/2)mv^2Kf = (1/2)(5 kg)(4 m/s)^2 = 40 JThe increase in kinetic energy is therefore:ΔK = Kf - Ki = 40 J - (1/2)(5 kg)(2 m/s)^2 = 4.4 JTherefore, the increase in kinetic energy of the body is 4.4 J.