How does the gravitational force vary throughout an elliptic orbit?

The gravitational force in an elliptical orbit is not constant but varies according to the distance between the orbiting body and the central body. This force is strongest at the periapsis due to the minimum distance between the two, providing the maximum gravitational pull, and weakest at the apoapsis, where the increased distance reduces the gravitational influence. This variability in gravitational force throughout the orbit is fundamental to the changing speeds and positions of the orbiting body, as it adheres to the laws of celestial mechanics.