Question

an object mass 20 kg and velocity 10 metre per second the mass of the object become double and velocity becomes half calculate the difference between final and initial kinetic energy

Answer 1

Explanation:

initial KE = 1/2*20*10^2= 1000 Joules

final KE = 1/2*40*5^2 = 500 Joules

difference = 1000-500 = 500 joule

Answer 2

Answer:

The difference between Final and initial Kinetic energy is 500 J

Explanation:

Given Mass = 20 kg

Velocity = 10 m/s

Case 1

Ek = 1/2 mv^2

    = 1/2 * 20 * 10 * 10 = 1000 J

Initial Ek = 1000 J

Case 2

Given mass is doubled = 2*20= 40 kg

Velocity is halved = 1/2 * 10 = 5 kg

Ek = 1/2 mv^2

     = 1/2 * 40 * 5 * 5 = 500 J

Final Ek = 500 J

Therefore Final Ek - Intial Ek = 500 - 1000 = -500 J