Question

The impulse given to a ball with mass of 2 kg is 16 N*s. If the ball starts from rest, what is its final velocity?

Answer 1

The impulse is equal to the variation of momentum of the object:

`I=\Delta p = m \Delta v`
where m is the mass object and
`\Delta v = v_f - v_i` is the variation of velocity of the object.

The ball starts from rest so its initial velocity is zero:
`v_i=0`. So we can rewrite the formula as

`I=m v_f`
or

`v_f = (I)/(m)`

and since we know the impulse given to the ball (I=16 Ns) and its mass (m=2 kg), we can find the final velocity of the ball:

`v_f = (16 Ns)/(2 kg)= 8 m/s`