Question

If the kinetic energy of rotation of a body is doubled then it's angular momentum

Answer 1

In fact momentum is mass multiplied by velocity. 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