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A rocket is moving up with a velocity up...

A rocket is moving up with a velocity `upsilon` if the velocity of this rocket is suddenly tripled, what will be the ratio of two kinetic energies ?

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`Initial KE = (1)/(2) mu^2`
`"Final" KE = (1)/(2)m upsilon^(2) = (1)/(2)m (3u)^2 = (9)/(2)mu^2 (as upsilon - 3u)`
Thus, `("initial" KE)/("final"KE) = (1/2"mu"^(2))/(1/9"mu"^(2))=1/9=1:9`.
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Knowledge Check

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