Rheostat, a device used to regulate an electric current by increasing or decreasing the resistance of the circuit. Some common uses of the rheostat are to dim lights, to control the speed of an electric motor, and to control the volume of a radio. The accompanying diagram shows a simple rheostat. Current flows into the resistance coil and from the resistance coil through the slider. When the control knob is turned, the slider moves along the coil; the amount of resistance is thus changed by varying the length of the current's path through the resistance coil.
Has this ever happened to you? The meteorologist calls for a massive snowstorm, but the flakes fail to arrive. Chaos theory can shed light on why forecasts fail (and why our orderly world may not be so orderly after all).
To the uninitiated, the LHC can look like a junk drawer ... a junk drawer that's full of tiny, rapidly decaying particles that move at light speed. How do scientists know what's where?