Shell Theorem

The Shell Theorem states that a spherically symmetric shell of mass exerts no gravitational force on objects located inside it. For objects outside the shell, the shell’s combined mass acts as if all that mass were concentrated at a single point at the center. This means that if you’re inside a hollow sphere, you feel no gravitational pull from the walls, and if you’re outside, you can treat the shell as a point mass for calculating gravitational effects. This theorem simplifies understanding gravitational interactions in spherical systems.