Ask A Scientist
Is “Lightning” electricity the same as what is in my outlets?
Asked by: Macy Johnson
School: Glenwood Elementary School
Teacher: Miss Brigham
Hobbies/Interests: Macy enjoys skiing, reading, and pets.
Career Interest: Author or illustrator
Answer from Mark Fowler
Professor at Binghamton University
Professor Fowler's research area is signal processing for networks of sensors. He enjoys playing the guitar and reading. Mr. Fowler has a wife and two daughters. You can check him out on the web at http://www.ws.binghamton.edu/fowler/.
Yes, they are the same thing! Atoms are the very small “building blocks” of stuff. Atoms themselves are made from even smaller particles; one type is called an electron and is a key to electricity. (Note: “electron” and “electricity” share six letters!) Imagine a scoop of chocolate chip ice cream: the chips are the electrons and the ice cream is the rest of the atom. Now imagine several soft, melty scoops (so that the chips are loose) sitting side by side. Then if I somehow push on the chips, I can move them from scoop-to-scoop. Inside the wires connected to an outlet, something “pushes” the electrons to flow from one atom to the next, and so on and so on. A battery can do the “pushing”, but the electricity from your outlet is “pushed” by a big machine called a generator at a power plant. This flow of electrons is what we call electricity!
Electricity can flow in a metal wire because its electrons are held weakly by the atoms (like in the soft ice cream). Such materials are called conductors. However, some other materials hold their electrons tightly (like if the ice cream were frozen solid) so it is hard to make electricity flow in them. But, if you “pushed” really hard you could still make it flow. Such materials are called insulators. The wires in your house have a metal conductor on the inside but are covered with a plastic insulator so the electricity goes only where we want it to go.
During a storm, the atoms at the top of a cloud have many of their electrons removed and they somehow end up at the bottom of the cloud. (I say “somehow” because scientists still don’t know for sure how this happens!) An interesting thing about electrons is that they can push away nearby electrons. So, the electrons on the cloud push away electrons on the ground. This makes what is like a really big and strong battery, with the cloud being one side of the “battery” and the ground being the other side. But the air in between is an insulator so it resists the flow of electricity. However, this REALLY strong “battery” eventually “pushes” so hard on the electrons in the air that it makes electricity flow… and that is lightening! This electricity is “pushed” so hard that it causes intense heat (you see it as the flash) and makes the air explode (you hear it as thunder).
So, in your house electricity flows through a conductor coated with an insulator and it goes where we want. In lightening it actually flows through an insulator (it can because it is being “pushed” so hard!) and we have no real control of where it will go! And… it is so much stronger than the electricity in your house that you can see it and hear it!