Question

boy off mass 2 kg makes an elastic collision with another boy rest and continues to move in lawrenceville direction with the speed equal to 1/3 of its original speed. find mass
of the second body​

Answer 1

Explanation:

Let mass of second body be m kg and its velocity after collision be v.

The collision is elastic i.e e=1

∴

u−0

3

u

−v

=−1 ⟹v=

3

4u

Applying conservation of momentum:

m

1

u+0=m

1

3

u

+mv

2u=2×

3

u

+m×

3

4u

⟹m=1 kg