Question

A bullet of mass m and velocity a is fired into a large block of wood of mass M The final velocity of the system is

Options

• `m/(m + M)a`

• `M/(m + M)a`

• `(m + M)/m a`

• `(m + M)/M a`

Answer 1

`m/(m + M)a`

Explanation:

Let final velocity be V.

Then momentum before collision is ma and that after collision will be (m + M)V

∴ ma = (m + M)V ⇒ V = `m/(m + M)a`.