Figure shows the orbit of a planet $P$ round the sun $S.$ $AB$ and $CD$ are the minor and major axes of the ellipse.

If $t_1$ is the time taken by the planet to travel along $ACB$ and $t_2$ the time along $BDA,$ then

Suppose the earth stopped rotating. Then, the weight a body will

A geo-stationary satellite is orbiting the earth at a height of $5R$ above surface of the earth, $R$ being the radius of the earth. The time period of another satellite in hours at a height of $2R$ from the surface of earth is

A particle of mass $M$ is situated at the centre of a spherical shell of same mass and radius $a$. The gravitational potential at a point situated at $\frac {a}{2}$ distance from the centre, will be

A particle of mass $M$ is at a distance $'a'$ from surface of a thin spherical shell of uniform equal mass and having radius $a$

A satellite is moving around the earth with speed $V$ in circular orbit of radius $r$ . If the orbital radius is decreased by $2\%$ , the speed of the satellite will