At a point very near to the earth's surface, the acceleration due to gravity is g. What will be the acceleration due to gravity at the same point if the earth suddenly shrinks to half its radius without any change in its mass?

At what height from the ground will be the value of $g$ be the same as

that in $10 km$ deep mine below the surface of earth.

Gravity meters measures in units of mGal where 1 Gal (or 1 galileo) is the C.G.S unit of acceleration due to gravity. A gravity meter shows a reading of +300 mGal at a place where the normal 'g' is 9.78 $m s^{-2}$. The correct 'g' at that place where the reading was taken is _____ $m s^{-2}$.

The gravitational potential difference between the surface of a planet and a point $20\ m$ above it is $16\ J/kg$. Then calculate the work done in moving a $4\ kg$ mass by $8\ m$ on a slope $60$ degree from the horizontal, is:

বিষুবীয় অঞ্চল থেকে মেরু অঞ্চলের দিকে অভিকর্ষীয় ত্বরণ-