A body is dropped from a height h . If it acquires a momentum p just before striking ground, then ma

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5.Work, Energy, Power and Collision

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A body is dropped from a height $h$ . If it acquires a momentum $p$ just before striking the ground, then the mass of the body is

A

$\frac{p}{{\sqrt {2gh} }}$

B

$\frac{{{p^2}}}{{2gh}}$

C

$\frac{{2gh}}{p}$

D

$\sqrt {\frac{{2gh}}{p}} $

Solution

Kinetic energy acquired by the body after falling through a height, $\mathrm{h}=$ loss of gravitational potential energy $=\mathrm{mgh}$

$O r$ $\frac{\mathrm{p}^{2}}{2 \mathrm{m}}=\mathrm{mgh} \quad \text { or } \quad \mathrm{m}=\frac{\mathrm{p}}{\sqrt{2 \mathrm{gh}}}$

Standard 11

Physics

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