How Do You Measure Electricity?

When you think of electricity, you think of wires, plugs, wall plates, hair dryers, appliances and all those other things that run on electric power. You probably never give much mind to the current of electricity running behind the scenes in the walls. Current is the flow of electricity; it is what moves it to make the things that you need to get the power they need to turn on. But what is the 'flow' that causes these things to get "powered on"?

It is just plain old physical science believe it or not! It is atomic particles that power your items such as your hair dryer every time you plug it in to the outlet and turn the switch on!

Think of it this way. Electricity is a stream of negatively charged particles, or molecules, called electrons, that flow through a conductor. In this case, the conductor, that which allows the flow of electrons to go through it, is wire, usually copper wire. The resistance of the wire to this stream of electrons is relatively low and is measured in ohms.

Therefore, electricity will go from one end of the wire right on through to the other end of the wire. That other end of the wire usually ends up in a receptacle in your wall in which you plug your electrical appliance. So, when you turn on any electrical appliance, (provided you paid your electric bill) you are engaging in a scientific experience!

But how much, or how many, of these negatively charged bits are coursing through that wire directly into your electric appliance? The rate of electrical flow, or current, is measured in amperes (amps). One amp is equivalent to 6.28 billion billion electrons going through a set point per second. It'sounds like there is a lot of pressure building up within that conductor. This brings me to another measurement.

This measurement is volts. The electrical pressure that causes electric current to flow through a conductor (wire, in this case) is measured in volts. I never knew that when someone said I would need a 120 volt line, or I would need a 240 volt line, they were really talking about the pressure within the conductor that would be needed to start up different electrical appliances. A light fixture only needs 120 volts; electric ranges and other heavy duty appliances need 240 volts.

The amount of power transported by a current under pressure to a lamp or any other electric appliance is measured in watts. The way we figure out the wattage is to multiply the amperes (current) by the volts (pressure). Let's figure that 1/2 amp of current at 120 volts will turn on a 60-watt bulb. A thousand watts equals one kilowatt. A kilowatt used for one hour is a kilowatt-hour (kwh). This is how the electric company measures our use of electricity and then bills us for what we use. It all sounds so simple. Not only are we involved in physical science, but also mathematics!

All this with just the flip of a switch!