Question

Gravitational field in a solid sphere
$x>r:x\le R:$
$E_G=\frac{-GM}{x^2}{E}_G=\frac{-GMx}{R^3}$.

Answer 1

For inside point i.e, $x<R$

${\overrightarrow{E}}_g\left(A\right)=-\frac{GM\overrightarrow{r}}{R^3}=\frac{-GMx}{R^3}$

For outside point i.e, $x\ge R$

Assume sphere as a point charge. So, ${\overrightarrow{E}}_g\left(P\right)=-\frac{GM}{x^2}$