Q. 103.9( 18 Votes )

# A rocket is moving up with a velocity v. If the velocity of this rocket is suddenly doubled, what will be the ratio of two kinetic energies?

Answer :

Initial velocity = v =v’= 2v

Initial kinetic energy =

Final kinetic energy (K.E.)

(K.E) initial : (K.E) final = 1:4

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