When string at B is cut, rod rotates about A.
Torque about A: τ=mg×2l
Moment of inertia about A: IA=3ml2
Angular acceleration: α=ml2/3mg⋅l/2=2l3g
Acceleration of COM: acm=α×2l=43g
Newton's second law: mg−T=macm
T=mg−43mg=4mg
JEE Main 2026 — Physics Mechanics
A uniform rod of mass m and length l suspended by means of two identical inextensible light strings as shown in figure. Tension in one string immediately after the other string is cut, is ____. (g acceleration due to gravity)

Held on 21 Jan 2026 · Verified 6 Jul 2026.
mg/4
mg/2
mg/3
mg
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