For many of us, static electricity is one of the earliest encounters we have with electromagnetism, and it’s a staple of high school physics. Typically, it’s explained as a product of electrons transferred in one direction between unlike substances, like glass and wool, or a balloon and a cotton T-shirt (depending on whether the demo is in a high school class or a kids’ party). Different substances have a tendency to pick up either positive or negative charges, we’re often told, and the process doesn’t transfer a lot of charge, but it’s enough to cause a balloon to stick to the ceiling, or to give someone a shock on a cold, dry day. (...)
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