Question

A hockey ball of mass 200g hits on with velocity 10 m/s what is change in momentum if ball bounce back on the same path with the same speed

Answer 1

Given,

• mass, $\displaystyle\sf{m=200\ g=0.2\ kg}$

• initial velocity, $\displaystyle\sf{\vec u=(10\ \hat i)\ m\ s^{-1}}$

• final velocity, $\displaystyle\sf{\vec v=(-10\ \hat i)\ m\ s^{-1}}$

Assume the impact is occurred in one dimensional motion.

Hence, the change in momentum,

$\displaystyle\longrightarrow\sf{\Delta p=m(\vec v-\vec u)}$

$\displaystyle\longrightarrow\sf{\Delta p=0.2(-10-10)\hat i}$

$\displaystyle\longrightarrow\sf{\underline{\underline{\Delta p=(-4\ \hat i)\ kg\ m\ s^{-1}}}}$