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A uniform rod of mass m=210kg and length l can rotate in vertical plane about a smooth horizontal axis hinged at point H. It is released from initial position making an angle of 37o with horizontal. Find force (in N) exerted by the hinge just after the rod is released from rest.
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Important Questions on Rotational Motion

MEDIUM

A mass m is supported by a massless string wound around a uniform hollow cylinder of mass m and radius R. If the string does not slip on the cylinder, with what acceleration will the mass fall on release?

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HARD
A solid disc of radius 20 cm and mass 10 kg is rotating with an angular velocity of 600 rpm, 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 10 s is _________π×10-1 N m
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[Given: The acceleration due to gravity g=10 m s2]

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HARD
A wheel of mass 10 kg and radius 0.8 m is rolling on a road with an angular speed 20rads-1 without sliding. The moment of inertia of the wheel about the axis of rotation is 1.2kgm2, then the percentage of rotational kinetic energy in the total kinetic energy of the wheel is ____________(approximately)
HARD

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HARD
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HARD
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EASY

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EASY
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HARD
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