The Earth moves around the Sun in an elliptical orbit as shown in the figure. The ratio $OA/OB = x$. The ratio of the speed of the Earth at $B$ to that at $A$ is nearly

If a satellite has to orbit the earth in a circular path every $6 \text{ hrs}$, at what distance from the surface of the earth should the satellite be placed (in $\text{ km}$)? (Radius of earth $R_e = 6400 \text{ km}$)
(Assume $\frac{GM}{4\pi^2} = 8 \times 10^{12} \text{ m}^3\text{s}^{-2}$, where $G$ and $M$ are the gravitational constant and mass of earth, and $10^{1/3} = 2.1$)

$A$ satellite of mass $\frac{M}{2}$ is revolving around the Earth in a circular orbit at a height of $\frac{R}{3}$ from the Earth's surface. The angular momentum of the satellite is $M \sqrt{\frac{GMR}{x}}$. The value of $x$ is . . . . . . ,where $M$ and $R$ are the mass and radius of the Earth,respectively. ($G$ is the gravitational constant)

$A$ 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:

The gravitational potential energy required to raise a satellite of mass $m$ to a height $h$ above the Earth's surface is $E_1$. Let the energy required to put this satellite into orbit at the same height be $E_2$. If $M$ and $R$ are the mass and radius of the Earth respectively,then the ratio $E_1: E_2$ is:

Which one of the following statements regarding an artificial satellite of the earth is incorrect?