By conservation of angular momentum at the point of contact
mr2ω0=mvr+mr2ω=mvr+mr2.v/r
⇒r2ω0=2vr⇒v=rω0/2
JEE Main 2013 — Physics Mechanics
A hoop of radius r and mass m rotating with an angular velocity ω0 is placed on a rough horizontal surface. The initial velocity of the centre of the hoop is zero. What will be the velocity of the centre of the hoop when it ceases to slip?
Held on 7 Apr 2013 · Verified 6 Jul 2026.
2rω0
rω0
4rω0
3rω0
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