OHMS

Imagine a pressurized water tank. Connect a narrow hose to it and open the valve. You'll get a certain flow of water because the hose is a certain size and length. Now the interesting part: make the hose twice as long, and the flow of water decreases by exactly two times. Makes sense? If we imagine the hose to have "friction", then by doubling its length, we double its friction. (The friction always doubles whether the water is flowing or not.) Make the hose longer and the water flows slower (fewer gallons per second,) make the hose shorter and the reduced friction lets the water flow faster (more gallons per second.) Now suppose we connect a very thin wire between the ends of a battery. The battery will supply its pumping pressure (its "voltage"), and this will cause the charge-stuff inside the thin wire and the charge-stuff within the battery to start moving. The charge flows in a complete circle. Double the length of the wire, and you double the friction. The extra friction cuts the charge flow (the amperes) in half. THE FRICTION IS THE "OHMS", IT IS THE ELECTRICAL RESISTANCE. To alter the charge-flow in a circle of wire, we can change the resistance of our piece of wire by changing its length. Connect a long thin wire to a battery and the charge flow will be slow (low amps.) Connect a shorter wire to the battery and the charge will be faster (high amps.) But we can also change the flow by changing the pressure. Add another battery in series. This gives twice the pressure-difference applied to the ends of the wire circle... which doubles the flow. We've just discovered "Ohm's Law:" Ohm's law simply says that the rate of charge flow is directly proportional to the pressure difference, and if the pressure goes up, the flow goes up in proportion. It also says that the resistance affects the charge flow. If the resistance goes up while the pressure-difference stays the same, the flow gets LESS by an "inverse" proportional amount. The harder you push, the faster it flows. The bigger the resistance, the smaller the flow (if the push is kept the same.) That's Ohm's law.