Practice question
Question
A solid sphere of mass 5kg and radius 0.3m rotates about an axis through its center. If its angular momentum is 9kg m2/s, what is its angular velocity?
Explanation
L = Iω. For a sphere: I = 25MR2 = 25×5×(0.3)2 = 0.18kg m2. ω = LI = 90.18 = 50rad/s. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 50 rad/s. This satisfies dimensional consistency and physical conditions given, so option C is scientifically correct.