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Question

A hollow cylinder of mass 1kg and radius 0.2m has a kinetic energy of 2J. What is its angular speed?

Options

Choose one · Correct answer highlighted

Explanation

I = MR2 = 1×(0.2)2 = 0.04kg m2. K = 12Iω2⇒2 = 12×0.04×ω2⇒4 = 0.04ω2⇒ω2 = 100⇒ω = 10rad/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 10 rad/s. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.