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A hollow sphere is rolling on a plane surface about its axis of symmetry. The ratio of rotational kinetic energy to its total kinetic energy is x5. The value of x is .
2
Hollow sphere: I = 23mR2; rolling: v = R
Krot = 12I 2 = 12 23mR2 v2R2 = 13mv2
Ktotal = 12mv2 + 13mv2 = 56mv2
KrotKtotal = 1/35/6 = 25
x = 2
Answer: 2
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