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A ball of mass 2 kg and another of mass 4 kg are dropped together from a 60 feet tall building. After a fall of 30 feet each towards earth, their respective kinetic energies will be in the ratio of
(3) 1 : 2
Kinetic energy gained after falling a height h from rest: K = mgh
Both fall the same height (30 feet):
K1K2 = m1m2 = 24 = 12
Answer: (3)
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