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प्रश्न
A rocket is moving up with a velocity v. If the velocity of this rocket is suddenly tripled, what will be the ratio of two kinetic energies?
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उत्तर
Let the mass of the rocket be m.
The kinetic energy of a rocket when it moves with velocity v,
`"K"_1 = 1/2"mv"^2`
The kinetic energy of rocket when it moves with velocity 3v,
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