Static electricity

Static electricity is electricity that is not going anywhere. It builds up on the surface of objects when they are rubbed together and waits there quietly for the most inconvenient possible moment, usually a car door or a handshake.^[1]

It is called static because it stays still. The moment it moves it becomes a spark, and is no longer static, which is why it never stays around to explain itself.

How it works

When two materials are rubbed together, electrons move from one to the other. One ends up with too many electrons and the other with too few, and the two spend the rest of the afternoon trying to settle up.^[2]

Rubbing a balloon on your hair moves electrons from the hair to the balloon. The balloon will then stick to a wall, and the hair will stick to everything else. Scientists call this the triboelectric effect, a name chosen so that nobody would ask any further questions.

Measurement

Walking across a carpet in a dry room can charge a person to several thousand volts. This sounds alarming until it is explained that the shock is over almost before it has begun. The International Bureau of Small Shocks has measured the average “ow” at 0.4 seconds, and the average time spent afterwards looking accusingly at the carpet at six seconds.^[3] On a much larger scale, the same thing happens inside a cloud, which has nobody to look at accusingly but tries anyway.

Prevention

• Humid air, which lets the charge leak away quietly instead of all at once.
• Touching a metal door handle with a key first, so that the key takes the shock and the hand takes the credit.
• Not rubbing things together, which rules out most of life.

See also

• Door – has a handle, which is where it happens
• Cloud – static electricity, but enormous
• Gravity – the other way of sticking things to things

References

1. Spark, S. (1985). Ow. Jolt Press. p. 1.
2. Wool, W. (2010). Rubbing It In. Fuzz Books.
3. International Bureau of Small Shocks (2002). “The Duration of Ow”. Revised after a carpet.