If the radius of the Earth decreases without any change in its mass,will the value of $g$ on its surface increase or decrease?

Write the equation of acceleration due to gravity at a height $h$ from the surface of the Earth,where $h << R_e$.

If the Earth loses its gravity,then for a body:

If the angular velocity of earth's spin is increased such that the bodies at the equator start floating,the duration of the day would be approximately ........ minutes
(Take: $g = 10 \, m/s^2$,the radius of earth,$R = 6400 \times 10^3 \, m$,Take $\pi = 3.14$)

Suppose that the force of earth's gravity suddenly disappears,choose the correct answer out of the following statements.

The rotation of the Earth (of radius $R$) about its axis speeds up to a value such that a man at latitude angle $45^{\circ}$ feels weightlessness. The duration of a day in such a case is