A body of mass m moving with velocity v makes a head-on collision with another body of mass 2m which is initially at rest. The loss of kinetic energy of the colliding body (mass m) is

Options :

1. 1/2 of its initial kinetic energy

2. 1/9 of its initial kinetic energy

3. 8/9 of its initial kinetic energy

4. 1/4 of its initial kinetic energy