Question

Two masses m and m/2
are connected at the two ends of a massless rigid rod of length l. The rod is suspended by a thin wire of torsional constant k at the centre of mass of the rod-mass system (see figure). Because of torsional constant k, the restoring torque is τ = kθ for angular displacement θ. If the rod is rotated by θ₀ and released, the tension in it when it passes through its mean position will be
(A) (3kθ₀²)/l
(B) (2kθ₀²)/l
(C) (kθ₀²)/l
(D) (kθ₀²)/2l
[JEE Main 2019]

Answer 1

Answer:

torsional constant k at the centre of mass of the rod-mass system (see figure). Because of torsional constant k, the restoring torque is τ = kθ for angular displacement θ. If the rod is rotated by θ₀ and released, the tension in it when it passes through its

Explanation:

(3kθ₀²)/l

(B) (2kθ₀²)/l

(C) (kθ₀²)/l

(D) (kθ₀²)/2l