Choose the correct statement from the following: Weightlessness of an astronaut moving in a satellite is a situation of

Assertion $A$: An astronaut inside a massive spaceship orbiting around the Earth will experience a finite but small gravitational force.
Reason $R$: The centripetal force necessary to keep the spaceship in orbit around the Earth is provided by the gravitational force between the Earth and the spaceship.

The period of revolution of a satellite is

Match the types of satellites in Column-$I$ with their applications in Column-$II$.

Column-$I$	Column-$II$
$(1)$ Polar satellite	$(a)$ Telecommunication
$(2)$ Geostationary satellite	$(b)$ Spying
	$(c)$ Weather forecasting

The speed of a satellite in a circular orbit of radius $R_0$ around the earth is $v_0$. Another satellite is in an elliptic orbit around the earth. If the minimum and maximum speeds of the second satellite are $\alpha v_0$ and $\beta v_0$ respectively,then its time period is

$A$ satellite is revolving very close to a planet of density $\rho$. The period of revolution of the satellite is