τ=ΔtΔL=ΔtI(ωf−ωi)
τ=Δt2mR2×[0−ω]
=210×(20×10−2)2×30×10600×π
=0.4π=4π×10−1
JEE Main 2021 — Physics Mechanics
A solid disc of radius 20cm and mass 10kg is rotating with an angular velocity of 600rpm, about an axis normal to its circular plane and passing through its centre of mass. The retarding torque required to bring the disc at rest in 10s is _________π×10−1Nm
Held on 25 Jul 2021 · Verified 6 Jul 2026.
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