Skip to content
Login Register

Practice question

MCQ

Question

A thin ring of mass 2kg and radius 0.4m has a kinetic energy of 8J. What is its angular speed?

Options

Choose one · Correct answer highlighted

Explanation

I = MR2 = 2×(0.4)2 = 0.32kg m2. K = 12Iω2⇒8 = 12×0.32×ω2⇒16 = 0.32ω2⇒ω2 = 50⇒ω = 50≈7.07rad/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 7 rad/s. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.

Related blogs

Guides and insights connected to this topic