A shel of mass M and radius R has point mass m placted at a distance r from its centre. The gravitational potential energy U(r) vs r will be

A shell of mass M and radius R has point mass m placed at a distance r from its centre. The gravitational potential energy U(r) vs r will be

A shell of mass M and radius R has another point mass m placed at a distance r from its centre (r gt R) . The force of attraction between the shell and point mass is :

A mass m is placed at point P lies on the axis of a ring of mass M and radius R at a distance R from its centre. The gravitational force on mass M is

A mass m is placed at point P lies on the axis of a ring of mass M and radius R at a distance R from its centre. The gravitational force on mass m is

Two spheres each of mass M and radius R are separated by a distance of r . The gravitational potential at the potential at the midpoint of the line joining the centres of the spheres is

Two spheres each of mass M and radius R are separated by a distance of r . The gravitational potential at the midpoint of the line joining the centres of the spheres is

Two spheres each of mass M and radius R are separated by a distance of r . The gravitational potential at the midpoint of the line joining the centres of the spheres is

A point mass m is placed inside a spherical shell of radius R and mass M at a distance R/2 form the centre of the shell. The gravitational force exerted by the shell on the point mass is

A point mass m is placed inside a spherical shell of radius R and mass M at a distance R/2 form the centre of the shell. The gravitational force exerted by the shell on the point mass is