Uniform Circular Motion

IMPORTANT

Uniform Circular Motion: Overview

This Topic covers sub-topics such as Centripetal and Centrifugal Force, Relation between Linear and Angular Velocity, Acceleration in Circular Motion, Resolution of Forces in Circular Motion and, Circular Motion with Variable Angular Acceleration

Important Questions on Uniform Circular Motion

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Two particles of mass M and m are moving in a circle of radii R and r. If their time – periods are same, what will be the ratio of their linear velocities?

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What is the linear velocity if the angular velocity vector is ω=3i^4j^+k^  and position vector is r=5i^6j^+6k^ ?

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A 500 kg car takes a round turn of radius 50 m with the velocity of  36kmhr1. The centripetal force is:

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A ball of mass 0.25 kg attached to the end of a string of length 1.96 m is moving in a horizontal circle. The string will break if the tension is more than 25 N. What is the maximum speed with which the ball can be moved?

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A body is whirled in a horizontal circle of radius 20 cm. It has an angular velocity of   10 rad s .  What is its linear velocity at any point on circular path

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When a body moves with a constant speed along a circle

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A particle of mass M is moving in a horizontal circle of radius R with uniform speed V. When it moves from one point to a diametrically opposite point, its :

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Two blocks of mass m1=10 kg and m2=5 kg, connected to each other by a massless inextensible string of length 0.3 m are placed along a diameter of a turn table. The coefficient of friction between the table and m1 is 0.5 while there is no friction between m2 and the table. The table is rotating with an angular velocity of 10 rad s-1 about a vertical axis passing through its centre O. The masses are placed along the diameter of the table on either side of the centre O such that the mass m1 is at a distance of 0.124 m from O. The masses are observed to be at rest with respect to an observer on the turn table. Calculate the frictional force on m1.

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A hemispherical bowl of radius R=0.1 m is rotating about its own axis (which is vertical), with an angular velocity ω. A particle of mass 10-2 kg on the frictionless inner surface of the bowl is also rotating with the same ω. The particle is at a height h from the bottom of the bowl.
Obtain the relation between h and ω. What is the minimum value of ω needed, in order to have a non-zero value of h ?

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Three particles, each of mass m, are situated at the vertices of an equilateral triangle of side length a. The only forces acting on the particles are their mutual gravitational forces. It is desired that each particle moves in a circle while maintaining the original mutual separation a. Find the initial velocity that should be given to each particle and also the time period of the circular motion.

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An electric line of force in the xy plane is given by the equation x2+y2=1. A particle with unit positive charge, initially at rest at the point x=1,y=0 in the xy plane, will move along the circular line of force.

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Spotlight S rotates in a horizontal plane with a constant angular velocity of 0.1 rad s-1. The spot of light P moves along the wall at a distance of 3 m. The velocity of the spot P when θ=45° (see. fig.) is 

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The tangential acceleration of the tip of a blade is 47.13 m/s2 and its centripetal acceleration is 473.9 m/s2. Find the value of linear acceleration of the tip of the blade.

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Why is centrifugal force considered as an imaginary force?

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A body of mass m is moving with speed V along a circular path of radius r. Now, the speed is reduced toV2  and radius is increased to 3r. For this change, initial centripetal force needs to he

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A particle is moving in a circle of radius R with a constant speed v. Its average acceleration over the time when it moves over half the circle is :

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Two identical particles each of mass m go round a circle of radius a under the action of their mutual gravitational attraction. The angular speed of each particle will be : 

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A child of mass 5 kg is going round a merry-go-round that makes 1 rotation in 3.14 s. The radius of the merry-go-round is 2 m. The centrifugal force on the child will be

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A particle is moving on a spiral path as shown in the figure. The speed of particle remains constant.

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In circular motion speed depends on angular position as v= θ+5 m/s. The value of θ as a function of time t is