Question

The kinetic energy of an object of mass m moving with a velocity of 5 ms-1 is 25 J what will be its kinetic energy if it is tripled ?

Answer 1

the K.E(KINETIC ENERGY) of the object is 25 J.

So,

25=1/2*m*(5)2

Therefore,m=2 kg.

Now, when the velocity is doubled, velocity becomes=2*5=10 m/s(ms-1)

So,

K.E.=1/2*2*(10)2 =100 J.

Now,when the velocity is increased three times,the velocity will be=3*5=15m/s

Therefore,K.E.=1/2*2*(15)2 = 225 J.