A person brings a mass of $1 \mathrm{kg}$ from infinity to a point $A$. Initially the mass was at rest but it moves at a speed of $2 \mathrm{m} {\mathrm{s}}^{-1}$ as it reaches $A$. The work done by the person on the mass is $-3 \mathrm{J}$. The potential at $A$ is

Taking the effect of bulging of earth and its rotation into account, consider the following statements:
(A) There are points outside the earth where the value of $g$ is equal to its value at the equator.
(B) There are points outside the earth where the value of $g$ is equal to its value at the poles.

The given figure shows the elliptical path of a planet about the sun. The two shaded parts have equal area. If $t_1$ and $t_2$ are the time taken by the planet to go from $a$ to $b$ and from $c$ to $d$ respectively. Then,

A person sitting in a chair in a satellite feels weightless because