Static electricity is all around us. We have all seen it, sometimes in funny and obvious ways, as in when our hair goes up in weird shapes and forms after we comb them, or when we get shocked after trying to open the door of our car.
Static electricity is one of the oldest scientific phenomena people observed and described. It comes as a result of the interactive force between electrical charges. So why is it called static electricity? It’s called “static” because the charges remain separated in one area rather than moving or “flowing” to another area as is the case of electricity flowing in a wire– called current electricity.
Static electricity has been known as far back as the ancient Greeks that things could be given a static electric “charge” (a buildup of static) simply by rubbing them, but they had no idea that the same energy could be used to generate light or power machines. It was Benjamin Franklin that helped bring electricity to the forefront. He believed electricity could be harnessed from lightning.
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But, what causes static electricity? At the atomic scale, negative charges are carried by tiny elementary particles called electrons. Most electrons are neatly packed inside the bulk of matter, whether it be a hard and lifeless stone or the soft, living tissue of your body. However, many electrons also sit right on the surface of any material. Each different material holds on to these surface electrons with its own different characteristic strength. If two materials rub against each other, electrons can be ripped out of the “weaker” material and find themselves on the material with stronger binding force. This transfer of electronsis what we know as a spark of static electricity.
Is it dangerous?
In addition to causing a painful shock, these sudden high-voltage discharges can provide a source of ignition for flammable substances, according to the Occupational Safety and Health Administration (OSHA). Static shock can also damage delicate electronics. According to NASA, a simple spark from a finger can damage sensitive components and render them unusable, so precautions must be taken such as keeping circuit boards in conductive plastic bags and wearing grounding straps to dissipate static charges continuously from your body.
Another source of static charge is the motion of fluids through a pipe or hose. If that fluid is flammable — such as gasoline — a spark from a sudden discharge could result in a fire or explosion. People who handle liquid fuels should take great care to avoid charge buildup and sudden discharge. In an interview, Daniel Marsh, professor of physics at Missouri Southern State University, warned that when putting gasoline in your car, you should always touch a metal part of the car after getting out to dissipate any charge that might have developed by sliding across the seat. Also, when buying gas for your lawnmower, you should always take the can out of your car and place it on the ground while filling it. This dissipates the static charge continuously and keeps it from building up enough to create a spark.
Sources: Discover Magazine, EdInformatics, Live Science
