The orbital angular momentum of a satellite revolving at a distance $r$ from the centre is $L.$  If the distance is increased to $4r$  then the new angular momentum will be

Masses and radii of earth and moon are $M_1,\, M_2$ and $R_1,\, R_2$ respectively. The distance between their centre is $'d'$ . The minimum velocity given to mass $'M'$ from the mid point of line joining their centre so that it will escape

Suppose, the acceleration due to gravity at the Earth's surface is $10\, m\, s^{-2}$ and at the surface of Mars it is $4.0\, m\, s^{-2}$. A $60\, kg$ pasenger goes from the Earth to the Mars in a spaceship moving with a constant velocity. Neglect all other objects in the sky. Which part of figure best represents the weight (net gravitational force) of the passenger as a function of time?

The rotation of the earth having $R$ radius about its axis speeds up to a value such that  a man at latitude angle $60^o$ feels weightlessness. The duration of the day in such a  case is.

Which of the following graph represents the variations of acceleration due to gravity $(g)$ with distance $r$ from the centre of earth?