Question

if the momentum of a body is doubled. then its kinteic energy in comparison to its initial kinetic energy will be changed to
a) Half
b) twice
c) one fourth
d) four times​

Answer 1

We know that K = P²/2m so K is directly proportional to p². therefore your answer will be four times.

That is D

Answer 2

D)Four Times

Kinetic energy of a body of given mass, is directly proportiional to its square of its velocity. When momentum is doubled, mass remaining constant, this means velcity is doubled. Hence, kinetic energy becomes 22=4 times i.e. say from 100 units to 400 units.