$A$ satellite is in a circular equatorial orbit of radius $r = 7000 \, km$ around the Earth. If it is transferred to a circular orbit of double the radius $(2r)$,then its angular momentum will:

Two stars of masses $m_1$ and $m_2$ are parts of a binary star system. The radii of their orbits are $r_1$ and $r_2$ respectively,measured from the centre of mass of the system. The magnitude of the gravitational force that $m_1$ exerts on $m_2$ is

Two particles of equal mass $m$ go around a circle of radius $R$ under the action of their mutual gravitational attraction. The speed of each particle with respect to their centre of mass is

What are the orbital period of the Moon around the Earth and the rotational period of the Moon about its own axis?

Consider a light planet revolving around a massive star in a circular orbit of radius $r$ with time period $T$. If the gravitational force of attraction between the planet and the star is proportional to $r^{-7/2}$,then $T^2$ is proportional to:

The orbital speed of an artificial satellite very close to the surface of the Earth is $V_o$. What is the orbital speed of another artificial satellite at a height equal to three times the radius of the Earth (in $,V_o$)?