When rod is rotated by angle α, the twist in the wire is ϕ.
angular frequency of wire, Ω=Ik
angular frequency of rod, ω=θ0.Ω
Max. Tension in the rod =mω2.3l
=mθ02.Ik.3l, here I=m3l2
=θ02lk
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…
JEE Main 2019 — Physics Mechanics
2019mcqmedium
Two masses m and 2m 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:
Official previous-year question
Held on 9 Jan 2019 · Verified 6 Jul 2026.
Options
- A
kθ02
- B
l3kθ02
- C
l2kθ02
- D
lkθ02
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