A body weighs $900$N on the earth. Find its weight on a planet whose density is $\dfrac{1}{3}^{st}$ the density of earth and radius is $\dfrac{1}{4}^{th}$ that of the earth.

In the figure it is shown that the velocity of lift is ;$2\;{\text{m}}{{\text{s}}^{{\text{ - 1}}}}$ while string ins winding on the motor shaft with velocity $2\;{\text{m}}{{\text{s}}^{{\text{ - 1}}}}$ and shaft A is moving downward with velocity $2\;{\text{m}}{{\text{s}}^{{\text{ - 1}}}}$ with respect lift, then find out the velocity of block B

The value of acceleration due to gravity on earth surface-

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 _____ $m s^{-2}$.

বিষুবীয় অঞ্চল থেকে মেরু অঞ্চলের দিকে অভিকর্ষীয় ত্বরণ-