Consider a thin uniform spherical layer of mass M and radius R. The potential energy of gravitational interaction of matter forming this shell is :

Consider a thin spherical shell of uniform density of mass M and radius R :

A particel of mass M is placed at the centre of a inform spherical shell of mass 2M and radius R. The gravitational potential on the surface of the shell is

A particle of mass m is placed at the centre of a unifrom spherical shell of mass 3 m and radius R The gravitational potential on the surface of the shell is .

A particle of mass m is placed at the centre of a unifrom spherical shell of mass 3 m and radius R The gravitational potential on the surface of the shell is .