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A Centrifuge

A centrifuge is a device used for separating solids and liquids, or liquids of different densities by spinning them at high speed so that the materials with the highest density travel towards the bottom of the centrifuge tube at a higher rate of speed than they would under the force of normal gravity (Centrifugation). The theory behind the centrifuge is a mechanical one. To separate materials of differing but closely related densities requires a force greater than that due to Earth's gravity. Random motion of molecules results in diffusion which may smear small differences in densities, so to overcome this and to speed up the process of separation, mass dependent forces are generated in a centrifuge by a spinning motion.

A body in motion tends to continue in motion along a straight line unless some force is exerted on it to change its path (Centrifugation). When a force is exerted on a body to make it go in a circle, an equal and opposite force will result pushing out from the center of the circle. This is known as the centripetal force and is equal to the mass of the object times the acceleration needed to keep it from flying outward in a straight line. Substances with a larger mass per unit volume will have a greater force exerted on them and will move towards the outer edge of the container more quickly than those of smaller mass.

In most cases, a centrifuge consists of a rotor into which samples in tubes are inserted, sitting on a somewhat wobbly shaft (Centrifugation). When a sample is to be centrifuged, it is always placed opposite a sample of comparable density on the opposite side of the rotor to prevent torque. There are three types of rotors: fixed angle rotors, swinging bucket rotors and vertical rotors. The most commonly used centrifuge has a fixed angle rotor. A swinging bucket rotor allows the sample to swing out to the horizontal, giving the maximum possible path of movement of particles, while the...

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A Centrifuge. (1969, December 31). In LotsofEssays.com. Retrieved 10:52, March 29, 2024, from https://www.lotsofessays.com/viewpaper/1703474.html