If the angular speed of the earth is doubled, the value of acceleration due to gravity (g) at the north pole

What will be the acceleration due to gravity at height $h$ if $h >> R$. Where $R$ is radius of earth and $g$ is acceleration due to gravity on the surface of earth

A man of $50\, kg$ mass is standing in a gravity free space at a height of $10\, m$ above the floor. He throws a stone of $0.5\, kg$ mass downwards with a speed $2\, m/s$. When the stone reaches the floor, the distance of the man above the floor will be ...... $m$

Imagine a new planet having the same density as that of earth but it is $3$ times bigger than the earth in size. If the acceleration due to gravity on the surface of earth is $g$ and that on the surface of the new planet is $g^{\prime}$, then

The mass of the moon is $(1/8)$ of the earth but the gravitational pull is $(1/6)$ of the earth. It is due to the fact that.

If mass of a body is $M$ on the earth surface, then the mass of the same body on the moon surface is