A gravitational force is the attractive force between two separate bodies. Gravity is related to mass so the more significant the mass, the greater the gravitational force it exerts on other objects. Also, the gravitational force of an object is dependent on distance. Gravity is where all things with mass or energy-including planets, stars, galaxies, and even light are brought toward one another. Another strong force on this earth is the nuclear force.
A strong nuclear force is what keeps the positively charged protons so close together in the nucleus of the atom. It is harnessed in atomic weapons, and to generate electrical energy in nuclear power plants. Force is an entity that pushes or pulls on a mass. Nuclear forces are only observable inside the nucleus of an atom as it holds protons and nucleons together.