Two equal masses $m$ and $m$ are hung from a balance whose scale pans differ in vertical height by $'h'$. The error in weighing in terms of density of the earth $\rho $ is
$\pi G\rho mh$
$\frac{1}{3}\pi G\rho mh$
$\frac{8}{3}\pi G\rho mh$
$\frac{4}{3}\pi G\rho mh$
If the radius of earth shrinks by $2 \%$ while its mass remains same. The acceleration due to gravity on the earth's surface will approximately.
The mass and diameter of a planet have twice the value of the corresponding parameters of earth. Acceleration due to gravity on the surface of the planet is ........ $m/{\sec ^2}$.
$Assertion$ : In a free fall, weight of a body becomes effectively zero.
$Reason$ : Acceleration due to gravity acting on a body having free fall is zero.
Two planets $A$ and $B$ of radii $R$ and $1.5 R$ have densities $\rho$ and $\rho / 2$ respectively. The ratio of acceleration due to gravity at the surface of $B$ to $A$ is :
A satellite revolves in the geostationary orbit but in a direction east to west. The time interval between its successive passing about a point on the equator is ........ $hrs$