What is electricity? Put as simply as I can – think of electricity as a type of energy. It can either build up and remain in one place (static electricity) or flow from one place to another (current electricity).
Let us learn a little more about current electricity. Movement of electrons (negatively charged particles of an atom) carries electrical energy from one place to another. This is called electrical current, which is often shortened to just “current”. Most people understand that electricity powers their electronics – from their phone and computer to their washer/dryer and car. But did you know that lightning is also a type of electrical current? It often occurs when negatively charged electrons (from pieces of ice bumping into each other), settle at the bottom of clouds during a storm. Since opposites attract, positively charged protons build up on the ground below the cloud, trying to make a connection to the electrons. These protons gather in anything that is sticking up from the ground (the closer to their opposite – the negative electrons in the clouds – the better). Eventually, when the protons climb high enough and the electrons descend low enough, they meet – causing lightning. Lightning can also occur within a cloud or between multiple clouds. Of course, the electrical current in your electronic devices lasts much longer than a bolt of lightning.
In order for an electrical current to occur, there has to be a compete circuit. This is a circle or other loop comprised of conductive materials. When you flip a light switch on, it completes a circuit connecting a source of electricity to a light bulb. Completing the circuit enables the electrical current to flow through the wires and power the light bulb. When the light switch is off, it breaks the circuit, which prevents a current from running through, and powering the light bulb. The same thing would happen if a rodent would chew through the wire – the circuit would be broken – and no electricity would be able to flow through it.
Electric current is measured in amperes, which are usually called amps, symbolized by A, and are named after Andrè-Marie Ampère. The number of negatively charged electrons passing through a section of a conductor in one second determines current. A current of one ampere means that one coulomb (defined as 6.24 x 1018) of charge passes through this section of conductor in one second.