# What is the value of g at the centre of the earth?

The value of g at depth $x$ from the surface of the earth is given by, $g’=\left(1-\frac{x}{R}\right)g$

At the centre of the earth, $x=R.$ So,

$g’=\left(1-\frac{R}{R}\right)g=(1-1)g=0$

Hence, the value of $g$ is zero at the centre of the earth.