$A$ body weighs $72 \ N$ on the surface of the earth. What is the gravitational force on it at a height equal to half the radius of the earth (in $N$)?

The depth at which the effective value of acceleration due to gravity is $\frac{g}{4}$ is

Acceleration due to gravity on the surface of Earth is $g$. If the diameter of Earth is reduced to one-third of its original value and mass remains unchanged,then the acceleration due to gravity on the surface of the Earth is . . . . . . $g$.

If the earth were to cease rotating about its own axis,the increase in the value of $g$ in the $C.G.S.$ system at a place of latitude of $45^{\circ}$ will be ........ $cm/sec^{2}$.

$A$ spring balance is graduated at sea level. If a body is weighed with this balance at consecutively increasing heights from the Earth's surface,the weight indicated by the balance:

If all objects on the equator of the earth feel weightless,then the duration of the day will nearly become ....... $hr$.