$A$ planet is revolving around the sun in an elliptical path as shown. The orbital velocity of the planet will be minimum at:

The time period of a geostationary satellite is $24 \; h$,at a height $6 R_{E}$ ($R_{E}$ is the radius of the Earth) from the surface of the Earth. The time period of another satellite whose height is $2.5 R_{E}$ from the surface will be:

Describe the Nicolaus Copernicus model for planetary motion.

$A$ planet revolves around the sun whose mean distance is $1.588$ times the mean distance between the earth and the sun. The revolution time of the planet will be ........... $years$.

If $A$ is the areal velocity of a planet of mass $M$,its angular momentum is

$A$ planet has an orbital radius twice that of the Earth's orbital radius. The time period of the planet is .......... $years$.