A man who is running has half kinetic energy of boy of half his mass. man speeds up by 1 , m/s and t

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5.Work, Energy, Power and Collision

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$A$ man who is running has half the kinetic energy of the boy of half his mass. The man speeds up by $1 \, m/s$ and then has the same kinetic energy as the boy. The original speed of the man was

A

$\sqrt 2 \,m/s$

B

$( \sqrt 2 - 1)\,m/s$

C

$2\, m/s$

D

$(\sqrt 2 + 1)\, m/s$

Solution

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Standard 11

Physics

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