Centrifugal force is an outward force associated with rotation. It was first described in a 1659 treatise called De vi centrifuga, by Dutch mathematician Christiaan Huygens. In 1666, another mathematician, Italian Giovanni Alfonso Borelli, illustrated the role of centrifugal force in the orbits of planets. However, it was English scientist Isaac Newton, the father of modern physics, who understood the profound nature of this force. Objects that move around something, such as a satellite moving around a planet, are subject to the influence of two opposing forces.

Centripetal force is the force that keeps an object moving along a curved or circular path, pushing it inwards. Gravity provides the centripetal force that keeps satellites in orbit. Centrifugal force pushes objects away from the center. This force depends on the velocity of the object, as well as its mass, that is, the quantity of matter in it. Higher mass and higher speed mean greater force. [Fcf = mv2/r] Centrifugal force is inversely proportionate to the distance between a body and the axis it rotates around. This means that the farther a body is from the rotational axis the less effect centrifugal force has. If the cause of the circular movement is a centripetal force, in other words a push towards the center capable of equalizing the centrifugal force, the body is forced to rotate around the center axis. This is one reason why planets in the solar system move in elliptical orbits around the sun.

Centrifugal force can be observed in everyday life. Driving offers one such example. When rounding a curve in a fast-moving car, centrifugal force pushes the passenger away from the curve. Centrifugal force comes into play frequently in sports. In hammer and discus throwing, for example, athletes spin around as fast as possible, gathering centrifugal force. The more force they build, the further the hammer or discus flies. Science and industry workers rely on machines called centrifuges. Centrifuges spin test tubes with liquids at high speeds. The resulting centrifugal force separates the different components in the solution, separating liquids from solids.