Kinematics of Rotation

IMPORTANT

Kinematics of Rotation: Overview

This topic consists of various concepts like Angular Velocity of a Rigid Body,Angular Velocity,Translational and Angular Acceleration, etc.

Important Questions on Kinematics of Rotation

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Angular position of a line of a disc of radius r=6 cm is given by θ=10-5t+4t2. The average angular speed (in rad s-1) between 1 s and 3 s is:

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θ=2t2+3t+1

Find ωav in 2 seconds

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Find the maximum height upto which disc can reach on the incline plane when given velocity v horizontally and disc is performing pure rolling motion.

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. A coin placed on a revolving disc, with its centre at a distance of 6 cm from the axis of rotation just slips off when the speed of the revolving disc exceeds 45 r.p.m. What should be the maximum angular speed of the disc, so that when the coin is at a distance of 12 cm from the axis of rotation, it does not slip?

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A rod of length 1 m is sliding in a corner as shown. At an instant when the rod makes an angle of 60° with the horizontal plane, the velocity of point A on the rod is 1 m s-1. The angular velocity of the rod at this instant is:

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the angular speed of earth around the Sun is 

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The velocity of the centre of mass of a solid sphere of radius R rotating with angular velocity about an axis passing through its centre of mass is

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A solid sphere is rolling down an inclined plane without slipping. If the inclined plane has inclination θ with the horizontal, then the coefficient of friction between the sphere and the inclined plane should be

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Relation between angular acceleration and linear acceleration.

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A block of mass M is released from rest on top of a smooth inclined plane of inclination θ. The block is connected to a light string which is wound over a disc shaped pulley of mass M and radius R as shown. If length of inclined surface is I, then time (in second) taken by the block to reach the bottom is-------------------(given:lgsinθ=3, in SI units)

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When a ceiling fan is switched off, its angular velocity reduces to 50% of its initial value while it makes 36 rotations. If angular retardation of the
fan is uniform, then how many more rotations will it make before coming to rest?
 

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A particle of mass m is whirled in horizontal circle with the help of two threads of length l each as shown in figure. Angular velocity equals ω, then

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The equation for angular displacement of a particle, moving in a circular path (radius 200 m) is given by:θ=18t+3t2-2t3 where θ is the angular displacement at the end of t sec. Find (i) angular velocity and acceleration at start, (ii) time when the particle reaches its maximum angular velocity, and(iii) maximum angular velocity of the particle.

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A disc of radius R is rolling without slipping with velocity v0 on a stationary surface. The radius of curvature of path of particle B at the position shown is B

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The speed of a particle in a circle is 2 m s-1 along the circumference of a circle of radius 0.5 m If the speed increases at the rate of 6 m s-2. The acceleration of the particle at a given instant  is 

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Find the height at which the string becomes slack
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A wheel of radius 1 m is spinning with angular velocity which varies with time as 5 t2 rad/s. The acceleration of the point on the wheel's rim at t=1 s, has the magnitude equal to _____.

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In 7s a car accelerates uniformly form rest to such a speed that its wheels are turning at a rate of 6 rω/s. How many revolutions does the wheel turn?

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A particle is moving with constant speed v along x-axis in positive direction. Find the angular velocity of the particle about the point 0,b, when position of the particle is a,0

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A particle is revolving about an axis with angular speed of 5π rad s-1. It comes to rest after 2.5 seconds. Angular speed of the particle after 2 seconds from the start is?