A satellite is to be stationed in an orbit such that it can be used for relay purposes (such a satellite is called a geostationary satellite) The conditions such a satellite should fulfill is / are

Our home planet the Earth suddenly shrinks in size, still remaining perfectly spherical, then which of the following is incorrect :

Radius of planet A is twice that of planet B and the density of A is one-third that of B. The ratio of the acceleration due to gravity at the surface of A to that at the surface of B is

A body is launched with a velocity less than escape velocity. The total mechanical energy is

In some region, the gravitational field is zero. The gravitational potential in this region