### Gravitation

goals
A solid sphere of mass $M$ and radius $R$ is surrounded by a spherical shell of same mass $M$ and radius $2R$ as shown. A small particle of mass $m$ is released from rest from a height $h(<< R)$ above the shell. There is a hole in the shell.
The Jupiter's period of revolution around the Sun is $12$ times that of the Earth.
The circular orbit of a stationary Earth's satellite remains motionless with respect to its surface.
A satellite revolves from east to west in a circular equatorial orbit of radius $R=1.00\times10^4\:km$ around the Earth.
For two balls of equal mass as shown in the figure, the magnitude of gravitational force between them if $F$: