Centrifuge

A centrifuge is a device for separating two or more substances from each other by using centrifugal force. Centrifugal force is the tendency of an object traveling around a central point to continue in a linear motion and fly away from that central point.

Centrifugation can be used to separate substances from each other becausematerials with different masses experience different centrifugal forces when traveling at the same velocityand at the same distance from the common center. For example, if two balls of different mass are attached to strings and swung around a common point at the same velocity, the ball with the greater mass will experience a greater centrifugal force. If the two strings are cut simultaneously, the heavier ball will tend to fly farther from the common center than will the lighter ball.

Centrifuges can be considered devices for increasing the effects of the earth's gravitational pull. For example, if a spoonful of clay is mixed vigorously with a cup of water and then allowed to sit for a period of time, the clay will eventually settle out because it experiences a greater gravitational pull than does the water. If the same clay-water mixture is centrifuged, however, the separation will take place much more quickly.