Physics - Gravitation Question with Solution | TestHub

According to Gauss's law for gravitation (or direct integration), the gravitational field inside a uniform spherical shell is zero. Since the point mass $m$ is placed at the center of the shell, it is inside the shell. Therefore, the gravitational field at its location due to the shell is zero.

The gravitational force experienced by a mass is given by $F=mE$, where $E$ is the gravitational field. Since $E=0$ inside the shell, the force $F$ experienced by the point mass $m$ is also zero.