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.
Booze, hooch, devil's brew. Whatever name you call it, alcohol is really just a combination of carbon, hydrogen and oxygen molecules. Test your knowledge of this simple compound with our quiz!
If a drugstore is the equivalent of a 7-Eleven where you can pick up ready-made apple pie pockets, then a compounding pharmacy is your corner bakery where an individual tart is made just for you. But are these specialized pharmacies safe?