Question

the kinetic energy of an object mass (m) moving with a velocity of 5 m /s is 25j, what will be its kinetic energy when its velocity is doubled ? what will be its kinetic energy when its velocity is increased three times

Answer 1

Kinetic energy is 1/2 MV^2

therefore 25 J = 1/2* M * 5m/s

= M =25*2/5*1 = 50/5 = = 10 

If velocity doubled means 

new V = 10 m/s

K.E = 1/2* 10 *10 = 100/2 = 50J

If new V is tripled means

New V = 15 m/s

K.E = 1/2 *15 * 10 = 150 / 2 = 75J

Hope it heps!!