A solid sphere of mass 4 kg and radius 0.30 m is suspended from a wire. The time  period of its angular oscillation if the torsional constant of the wire is   6×10−3  Nm/rad

For torsional pendulam,time period is T=2πIc for solid sphere moment of inertia =2MR25 T=2π2MR25chere I = moment of inertia; c= couple per unit twistT=2π2×4×0.325×6×10−3T=4π6T=4π2.44=30.76   sec