The classic example of gravitational force is that of an apple falling from a tree. Once its stem breaks, the apple accelerates toward the Earth's center of gravity at a rate of 9.8 m/s^2. The effect of gravity is observ... More »

Earth's gravitational force refers to the force imposed on any object close to Earth as a result of Earth's mass. Any object that is close to the Earth experiences gravity. For example, when a ball or an object is thrown... More »

The gravitational force of Mars is 38 percent of Earth's gravity. This low gravity is due to the fact that Mars only possesses 11 percent of the Earth's mass and 15 percent of the Earth's volume. The planet's significant... More » Science Astronomy Planets

Gravitational pull is the invisible force that causes massive objects to pull other objects towards them. For instance, when a person jumps up in the air, it is the earth’s gravitational pull that causes him to return to... More »

As the distance between two objects decreases, the gravitational force between them increases. Conversely, as the distance between them increases, the gravitational force decreases. Gravitational force is inversely propo... More »

An example of mechanical force is the thrust of an airplane. The airplane's engines make use of a propulsion system, which creates a mechanical force or thrust. Without thrust, an aircraft cannot move in the air. More »

A moment arm is the distance between the joint axis and the line of force acting on the joint; an example is using a wrench to loosen a nut, the wrench acts as a moment arm and produces more force than trying to free the... More »