Question

lf linear momentum of a body increases by x%.then the increase in the kinetic energy of the body will be?

Answer 1

Momentum= m*v
and KE= 1/2*m*v*v
Change in momentum will be due to change in velocity of a body
if momentum= 75/100=1/4
than Ke= 75/100*v*1/2= 1/8v

Answer 2

Suppose the original momentum of the body to be ‘p’ and a 50% increase leads to amomentum of p+(50/100)p=1.5p

The relation between momentum ‘p’ and kinetic energy ‘k’ is p^2=2km (m is mass of object) hence k=(p^2)/2m

New kinetc energy

k' = ((1.5p)^2)/2m ( as new p is 1.5p)

k'=2.25*((p^2)/2m) =2.25*k

So, kinetic energy increased by 125%