Two identical uniform rods, each of mass m and length l, form an L-shaped system resting on a peg P as shown. If displaced by a small angle in its plane, find the period of oscillations.

Question

G1 Physics · Accepted Answer

For the L-shaped pair of rods, total moment of inertia about peg P is I=2(ml²/3)=2ml²/3. The combined centre of mass is at distance h=l/(2√2) from P and total mass is 2m. Hence T=2π√[I/(2mgh)]=2π√(2√2 l/3g). Correct answer: B.