The ratio of the distances of two planets from the sun is $1.38$. The ratio of their period of revolution around the sun is

Let the speed of the planet at the perihelion Pin Figure be $v_{p}$ and the Sun-planet distance $SP$ be $r_{ P }$ Relate $\left\{r_{P}, v_{P}\right\}$ to the corresponding quantities at the aphelion $\left\{r_{A}, v_{A}\right\} .$ Will the planet take equal times to traverse $B A C$ and $C P B ?$

A binary star system consists of two stars one of which has double the mass of the other. The stars rotate about their common centre of mass :-

The time period of an artificial satellite in a circular orbit of radius $R$ is $2\, days$ and its  orbital velocity is $v_0$. If time period of another satellite in a circular orbit is $16 \,days$ then

A satellite revolving around a planet in stationary orbit has time period 6 hours. The mass of planet is one-fourth the mass of earth. The radius orbit of planet is : (Given $=$ Radius of geo-stationary orbit for earth is $4.2 \times 10^4 \mathrm{~km}$ )