System of Parti...

The position of axis of rotation of a body is changed so that its moment of inerted decreases by 36%. The % change in the radius of gyration is  

Four rings each of mass $$M$$ and radius $$R$$ are arranged as shown in the figure. The moment of inertia of the system about the axis $$yy'$$ is 

Three identical thin rods each of length l and mass M are joined together to from a letter H. What is the moment of intertia of the system about one of the sides of H

A particle of mass M kg describes a circle of radius 1 m. The centripetal acceleration of the particle is $$ 4m/s^2 $$. What will be the momentum of the particle ?

A circular disc of M.I. 10 $$kg-m^2$$ rotates about its own axis at a constant speed of 60 r.p.m. under the action of an electric motor of power 31.4 W. If the motor is switched off, how many rotations will it cover before coming to rest?

Two particles of equal mass 'm' go around a circle of radius R under the action of their mutual gravitation attraction. The speed of each particle with respect to their centre of mass is :

A football roots through the ground. The path followed by centre of mass of football is 

Two bodies of masses $$2kg$$ and $$4kg$$ are moving with velocities $$2m/s$$ and $$10m/s$$ respectively towards each other due to mutual gravitational attraction. What is the velocity of their centre of mass (Bodies are at rest initially) :

A thin circular ring first slip down a smooth incline then rolls down a rough incline of identical geometry from the same height. The ratio of time taken in the two motion is :

Two spherical bodies of mass $$M$$ and $$5M$$ and radii $$R$$ and $$2R$$ respectively are released in free space with initial separation between their centers equal to $$12R$$. If they attract each other due to gravitational force only, then the distance covered by the smaller body just before the collision is