Angular Momentum and its Conservation

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Angular Momentum and its Conservation: Overview

This topic covers concepts such as Angular Momentum, Angular Momentum of Particle about a Fixed Point, Angular Momentum of a Rigid Body in Pure Rotation, Conservation of Angular Momentum, etc.

Important Questions on Angular Momentum and its Conservation

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A planet of mass m is in an elliptical orbit about the sun m<<Msun with an orbital period T. If A be the area of orbit, then its angular momentum would be

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When a mass is rotating in an orbit about a fixed axis, its angular momentum is directed

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Kepler's second law regarding constancy of areal velocity of a planet is a consequence of conservation of

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Consider a particle of unit mass being thrown with an initial velocity v0 making an angle ϕ with the horizontal ground. What is the magnitude of the angular momentum of the particle about the point of projection at a time t after its projection while it is in fight?

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Particles of mass m1 and m2 initially sitting at the same position, start moving simultaneously at t=0 with velocities v1 and v2, respectively. After a time t=t0 the angular momentum of the particle of mass m2 with respect to the particle of mass m1 is

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A planet of mass m moves in an elliptical path around the Sun (which is at one of the foci of the ellipse), so that its maximum and minimum distances from the Sun are rmax and rmin , respectively. Taking the gravitational constant to be G and the mass of the Sun to be Ms, what is the angular momentum of the planet relative to the centre of the Sun?

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A bob of mass m attached to an inextensible string of length l  is suspended from a vertical support. The bob rotates in a horizontal circle with an angular speed ω  rad/s about the vertical. About the point of suspension :

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A cubical block of side 30 cm is moving with velocity 2 m s-1 on a smooth horizontal surface. The surface has a bump at a point O as shown in the figure. The angular velocity (in rad s-1) of the block immediately after it hits the bump, is:

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A child is standing with folded hands at the centre of a platform rotating about its central axis. The kinetic energy of the system is K. The child stretches his arms so that the moment of inertia of the system doubles. The kinetic energy of the system now is

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Given r=4j^ and p=2i^+3j^+k^ . The angular momentum is

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Which of the following physical quantity is represented by the product of the moment of inertia and angular velocity? 

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A solid sphere is rotating in free space. If the radius of sphere is increased keeping mass same which one of the following will not be affected?

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A ball of mass 160 g is thrown up at an angle of 60° to the horizontal at a speed of 10 m s-1. The angular momentum of the ball at the highest point of the trajectory with respect to the point from which the ball is thrown is nearly g=10 m s-2

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A uniform rod AB of length L and mass M is lying on a smooth table. A small particle of mass m strikes the rod with velocity v0 at point C at a distance x from the centre O. The particle comes to rest after collision. The value of x, so that the point A of the rod remains stationary just after the collision, is L/n, then find n.

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An object of mass 2 kg is projected from ground, with initial velocity 40 m s-1, making angle 60° with the horizontal. Find its angular momentum about the point of projection when the object is at its maximum height. (Take g=10 m s-2)

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A uniform rod AB of length L and mass M is lying on a smooth table. A small particle of mass m strikes the rod with velocity v0 at point C at a distance x from the centre O. The particle comes to rest after collision. If the value of x, so that the point A of the rod remains stationary just after the collision, is L/n, then find n.

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What is Angular momentum of a particle?

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A horizontal disc is freely rotating about a vertical axis passing through its centre at the rate of 100 rpm. A  bob of wax of mass 20 g falls on the disc and sticks to it a distance of 5 cm from the axis. If the moment of inertia of the disc about the given axis 2×10-4  kg m2. Find the new frequency of the disc.

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State the law of conservation of Angular momentum.

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As shown in the figure, two balls of same mass m are situated at the centre of a tube of mass M and are rotating with a uniform angular velocity ω0. If the balls suddenly come to end of the tube the resultant angular velocity will be :

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