Get Answers to all your Questions

header-bg qa

A ball of mass m falls vertically to the ground from a height \mathrm{h_{1}} and rebounds to a height \mathrm{h_{2}}. The change in momentum of the ball on striking the ground is :-

Option: 1

\mathrm{m \sqrt{2} g\left(h_1+h_2\right)}


Option: 2

\mathrm{n \sqrt{2 g\left(m_1+m_2\right)}}


Option: 3

\mathrm{m g\left(h_1-h_2\right)}


Option: 4

\mathrm{m\left(\sqrt{2 g h_1}-\sqrt{2 g h_2}\right)}


Answers (1)

best_answer

Let V_1 = Velocity when height of free fall is \mathrm{h_1}

    \mathrm{V_2} = Velocity when height of free rise is \mathrm{h_2}

\mathrm{\therefore \quad v_1^2=u^2+2 g h_1} for free fall

Or       \mathrm{\therefore \quad v_1^2=0+2gh}=2gh

For free rise after impact on ground

                    \mathrm{ 0=V_2^2-2 g h_2 \text { or } V_2^2=2 g h_2}

\mathrm{ Initial\: \: momentum =m v, }

\mathrm{ Final \: \: momentum =m v_2 }

Now, change in momentum \mathrm{ \begin{aligned} & =m\left(V_1-V_2\right) \\ & =m\left(\sqrt{2 g h_1}-\sqrt{2 g h_1}\right) \end{aligned} }

 

Posted by

SANGALDEEP SINGH

View full answer

NEET 2024 Most scoring concepts

    Just Study 32% of the NEET syllabus and Score up to 100% marks