Static electricity

Static electricity is, above all, fun, but it also can be annoying at times. I was at a conference in Queenstown last week, and was haunted by static everywhere I went. I’m guessing that atmospheric conditions were pretty dry, meaning that electric charge didn’t leak away quickly. When you know that you are going to get a shock when you press the lift call button at the hotel it makes you behave in odd ways. I’m sure someone watching on a security camera must have wondered what I was up to.

A Van der Graaf generator would have worked a treat, but I forgot to pack one.

I had one incident with a lolly (sweet, candy, depending on your origin) wrapper. It stuck to me and wouldn’t budge. I could swipe it from my clothes, but then it stuck to my hand. I could then transfer it from one hand to another, or back to my clothes. But I couldn’t shake it off. It was well and truly attached.

Electric charge sits on the surface of objects. That means the amount an object acquires is broadly proportional to its surface area. That makes small objects particularly susceptible to its effects. The force of gravity on an object is clearly proportional to its mass (density times volume), so the relative strength of the electrostatic force compared to the gravitational force is proportional to the surface to volume ratio.  Small objects have a much greater ratio than large objects. A lolly wrapper therefore glues itself to you, whereas a chair just gives you a shock.



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