The satellite of mass $m$ revolving in a circular orbit of radius $r$ around the earth has kinetic energy $E$. Then its angular momentum will be

The period of revolution of planet $A$ around the sun is $8$ times that of $B$. The distance of $A$ from the sun is how many times greater than that of $B$ from the sun

A satellite which is geostationary in a particular orbit is taken to another orbit. Its distance from the centre of earth in new orbit is $2$ times that of the earlier orbit. The time period in the second orbit is

During motion of a planet from perihelion to aphelion the work done by gravitational force of sun on it is ...........

What does not change in the field of central force

The time period of a satellite of earth is $24$ hours. If the separation between the earth and the satellite is decreased to one fourth of the previous value, then its new time period will become $.......\,hours$