Question

the momentum of a body is increased by10% . The percentage change in its kinetic energy is nearly

Answer 1

k=m x v x v/2
momentum(P)=m x v
so,
k=P x v/2
new P = P+10/100 x P
           = P x 11/10
new K=11/10 x P x v/2
          =11/10 k
increase  =K-k=1/10 k
percent increase = 1/10k/k x 100
                            =10 percent increase