Question

Two bodies of masses m1 and m2 have the same linear momentum. What is the ratio of their kinetic energies?

Answer 1

so given m1v1=m2v2
v1/v2 = m2/m1

K1/K2 = (1/2m1v1²)/(1/2m2v2²)

K1/K2 = (m1/m2)/(v1/v2)²
K1/K2 = (m1/m2)/(m2/m1)²
K1/K2 = m2/m1 ANSWER

Answer 2

momentum of two bodies of masses m1 andm2=m1v1=m2v2      k.e of the 1st body=1/2m1v1*2 k.e of the 2nd body=1/2m2v2*2 ratio of their k.e=k1/k2            ie     k1/k2 =1/m1v1*2/1/2m2v2*2=m1/m2 x(v1/v2)*2 butv1/v2=m2/m1    then k1/k2=m1/m2 x(m2/m1)*2 =m2/m1       therefore ratio of k=m2/m1