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Question
For the same kinetic energy of a body, what should be the change in its velocity if its mass is increased nine times?
Solution
Let initial mass m1 = m, initial velocity v1 = v
Final mass m2 = 4m, Find velocity = v2
For the same kinetic energy,
`1/2`m1v12 = `1/2` m2v22 or `1/2` mv2 =`1/2` × 9m × v22
v2 =`sqrt(1/9"v"^2)=1/3"v".`
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