Question

1. Object A has a momentum of 10 Ns and object B has a momentum of 3 Ns. They collide, and after the collision object A has a momentum of 5 Ns. How much momentum will object B have after the collision?

Answer 1

Given,

The momentum of object A before the collision, p₁=10 Ns

The momentum of object B before the collision, p₂=3 Ns

The momentum of object A after the collision, p₃=5 Ns

From the law of conservation of momentum, the total momentum of a system always remains constant. Thus the total momentum of the objects before the collision must be equal to the total momentum of the objects after the collision.

Thus,

$p_1+p_2=p_3+p_4$

Where p₄ is the momentum of object B after the collision.

On substituting the known values,

$\begin{gathered} 10+3=5+p_4 \\ \Rightarrow p_4=10+3-5 \\ =8\text{ Ns} \end{gathered}$

Thus the momentum of the object B after the collision is 8 Ns