What is gravitational force defined as?

Gravitational force is defined as an attractive force between two masses. This fundamental concept is rooted in Newton's law of universal gravitation, which states that every point mass attracts every other point mass in the universe with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers. This means that more massive objects exert a stronger gravitational pull on each other, and as the distance between the masses increases, the gravitational force decreases.

The other options present incorrect characterizations of gravitational force. For instance, a repulsive force is not consistent with gravitational interactions, which are inherently attractive. Additionally, the assertion that gravitational force is a constant force independent of mass overlooks the essential relationship defined by Newton's law, where the force varies with the mass of the objects involved. Lastly, it is inaccurate to claim that gravitational force only operates in a vacuum; it acts on masses regardless of the medium in which they are located, including air, water, and solid materials. Thus, the accurate definition aligns with the nature of gravitational forces as attracting between masses.