Some Basic Facts about Electricity

Here are a few basic facts you should know about electricity.

The three important things to measure are:

Voltage (Think of this as electricity pressure)  (Sometimes denoted by E for Electromotive Force, and measured in units called Volts)

Current (Think of this a the flow of electricity) (Some times denoted by I, and measured in Amps, A)

Resistance (Think of this as the “bottleneck” or resistance to current flow) (Sometimes denoted by R, and measured in Ohms)

There is DC (Direct Current Flow, one way) and AC (Alternating Current, two way.  The voltage and current fluctuate up and down, positive and negative, and look like what is called a Sine Wave)

With AC electricity, Resistence is called Impedence (denoted by Z)

There is a universal relationship you will learn that relates Voltage, Current, and Resistance that is called

Ohm’s Law.  It is:    Voltage = Current x Resistance,

Or  E = IR.  There is a similar relationship for AC electricity.

So, You can see if E is constant  I and R move in opposite directions.

One last comment.  There are prefixes sometimes used.  Kilo means thousands, Mega means millions, milli means thousandths, and micro means millionths.

Now with Ohm’s Law  1 Volt = 1 Amp x 1 Ohm.

But also,  1 Volt = 1 milliAmp x 1 KiloOhm = 1 micro Amp x 1 Mega Ohm

In the Killinger’s Practical Electricity you will see all of these things discussed plus much much more.  If you are interested in Electricity for practical purposes or just want to be better educated, this will be an excellent investment.

To learn how to work safely with electricity see Practical Electricity for Non-Electricians