Question

A 3 kg object moves to the left with a speed of 10 m/s. The object strikes a wall and rebounds with a speed of 5 m/s to the right. What impulse is applied to the object?

Answer 1

Given data:

* The mass of the object is 3 kg.

* The speed of the object towards left is 10 m/s.

* The speed of the object towards right is 5 m/s.

Solution:

The impulse applied to the object is,

$J=m(v-u)$

where v is the final velocity towards right, u is the initial velocity left, and m is the mass of the object,

By taking the velocity positive towards right and negative towards left, the impulse acting on the object is,

$\begin{gathered} J=3(5-(-10)) \\ J=3(5+10) \\ J=45\text{ kgm/s} \end{gathered}$

Thus, the impulse applied on the object is 45 kgm/s.