`T_(1)=2pisqrt((L)/(g))and T_(2)=2pisqrt((I)/(C))`
hwere `I=` moment of inertia of the rod about an axis through th pivot `=(1)/(3)mL^(2)` and `C=` restoring torque per unit angular displacement `=mgL//2`
`:. T_(2)=2pisqrt(((1//3)mL^(2))/(mgL//2))=2pisqrt((2L)/(3g))`
`:. (T_(1))/(T_(2))=sqrt((3)/(2))`