If suddenly the gravitational force of attraction between earth and a satellite revolving around it becomes zero, then the satellite will

move towards the earth

Using Principle of conservation of energy

$-\frac{GMm}{R}+\frac{1}{2} m\left(\frac{v_{e}}{r}\right)^2=-\frac{GMm}{R+h}$

where $v_e=\sqrt{\frac{2 G M}{R}}$

or $-\frac{GMm}{R}+\frac{1}{2} \frac{mv_{e}^2}{4}=-\frac{GMm}{R+h}$

or $\frac{G M m}{R}+\frac{1}{8} m\left(\frac{2 G M}{R}\right)=-\frac{G M m}{R+h}$

or $-\frac{1}{R}+\frac{1}{4 R}=-\frac{1}{R+h}$ or $-\frac{3}{4 R}=-\frac{1}{R+h}$

or $3 R+3 h=4 R ; h=\frac{R}{3}$