Two masses M and M/2 are joined together by means of light inextensible string passed over a frictionless pulley as shown in the figure. When the bigger mass is released, the small one will ascend with an acceleration of
g
In elastic collision
both momentum and kinetic energies are conserved
both momentum and kinetic energies are not conserved
only energy is conserved
only mechanical energy is conserved
A.
both momentum and kinetic energies are conserved
In elastic collision both momentum and kinetic energies are conserved
A ball is released from the top of a tower. The ratio of work done by force of gravity in first, second and third second of the motion of the ball is
1 : 2 : 3
1 : 4 : 9
1 : 3 : 5
1 : 5 : 3
Three identical spheres, each of mass 1 kg are kept as shown in figure below, touching each other, with their centres on a straight line. If their centres are marked P,Q, R respectively, the distance of centre of mass of the system from P is
The moment of inertia of a thin rod of mass M and length L, about an axis perpendicular to the rod at a distance from one end is
A body rolls down an inclined plane. If its kinetic energy of rotation is 40% of its kinetic energy of translation, then the body is
solid cylinder
solid sphere
disc
ring
Which of the following statements about the gravitational constant is true ?
It is a force
It has no unit
It does not depend on the nature of the medium in which the bodies are kept
It depends on the value of the masses
Four particles each of mass M, are located at the vertices of a square with side L. The gravitational potential due to this at the centre of the square is
zero
Two identical solid copper spheres of radius R are placed in contact with each other. The gravitational attraction between them is proportional to
R2
R-2
R4
R-4