The orbital speed of Jupiter is

$A$ satellite is orbiting the Earth in a circular orbit of radius $r.$ Which of the following statements is correct?

$A$ spaceship approaches the moon (mass $= M$,radius $= R$) along a parabolic path which is almost tangential to its surface. At the moment of maximum approach,the brake rocket is fired to convert the spaceship into a satellite of the moon. Find the change in speed.

$A$ satellite of mass $m$ is circulating around the Earth with constant angular velocity. If the radius of the orbit is $R_0$ and the mass of the Earth is $M$,the angular momentum about the centre of the Earth is:

$A$ satellite $S$ moves around a planet $P$ in an elliptical orbit as shown in the figure. The ratio of the speed of the satellite at point $a$ to that at point $b$ is:

Imagine a light planet revolving around a very massive star in a circular orbit of radius $R$ with a period of revolution $T$. If the gravitational force of attraction between the planet and the star is proportional to $R^{-5/2}$,then,