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.
Imagine walking through a field and stumbling upon scads of corpses, all in various states of decomposition. It's not the setting for your next nightmare, but rather a very real discipline of forensic anthropology.
The Large Hadron Collider sounds so exciting, with its millions of near-light-speed collisions per second. But what do scientists really see while that's going on?