An object has momentum p & kinetic energy E . If its momentum becomes 2,p then its kinetic

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5.Work, Energy, Power and Collision

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An object has momentum $p$ & kinetic energy $E$. If its momentum becomes $2\,p$ then its kinetic energy will be :-

A

$\frac{E}{2}$

B

$3\,E$

C

$2\,E$

D

$4\,E$

Solution

$\frac{E=\frac{p^{2}}{2 m}}{E^{\prime}=\frac{(2 p)^{2}}{2 m}}$

$\therefore \quad \frac{E}{E^{\prime}}=\frac{1}{4}$

$E^{\prime}=4 E$

Standard 11

Physics

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