- published: 26 Mar 2016
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A parachute is a device used to slow the motion of an object through an atmosphere by creating drag, or in the case of ram-air parachutes, aerodynamic lift. Parachutes are usually made out of light, strong cloth, originally silk, now most commonly nylon. Parachutes must slow an object's terminal vertical speed by a minimum 75% in order to be classified as such. Depending on the situation, parachutes are used with a variety of loads, including people, food, equipment, space capsules, and bombs.
Drogue chutes are used to aid horizontal deceleration of a vehicle (a fixed-wing aircraft, or a drag racer), or to provide stability (tandem free-fall, or space shuttle after a touchdown).
The word "parachute" comes from the French prefix paracete, originally from the Greek, meaning to protect against, and chute, the French word for "fall", and it was originally coined, as a hybrid word which meant literally "that which protects against a fall", by the French aeronaut François Blanchard (1753–1809) in 1785.
The future is the indefinite time period after the present. Its arrival is considered inevitable due to the existence of time and the laws of physics. Due to the nature of the reality and the unavoidability of the future, everything that currently exists and will exist can be catagorized as either permanent meaning that they will exist for the whole of the future or temporary meaning that they won't and thus will come to an end. The future and the concept of eternity have been major subjects of philosophy, religion, and science and defining them non-controversially has consistently eluded the greatest of minds. It is the opposite of the past, and is the time after the present. In the Occidental view, which uses a linear conception of time, the future is the portion of the projected time line that is anticipated to occur. In special relativity the future is considered to be absolute future or the future light cone. In physics, time is considered to be the fourth dimension of the universe.