MadSci Network: Physics |
Hi Heidi!
Electrostatic "zaps" become common when humidity is low, and they go away again when humidity is high. In the USA, the problem typically occurs during the winter. In a home, a humidifer can help reduce the problem.
Humidity makes a difference because, when the air is humid, water is adsorbed onto the surfaces of all objects. This makes them slightly conductive, even if they are electrical insulators such as plastic or cloth. When dissimilar insulators touch or rub together, a separation of "static" charge occurs. However, when conductors touch or rub together, there's little or no charging. Humid conditions makes insulators act conductive.
Under dry conditions, the insulators become insulating again, and you can charge up your body by walking or scuffing on the carpets.
It's impossible to humidify the whole world. In some cases you can eliminate the problem by laundering your clothes with a fabric softener which contains anti-static ingredients. (The ingredients usually are chemicals which attract water out of the air and make cloth surfaces slightly damp.) You can also teach yourself a new behavior: knock your knuckles against anything you're about to touch. The "zap" will still occur, but your knuckles are much less sensitive than your fingertips.
Here is a bit more info:
http://www.amasci.com/emotor/zapped.html
http://www.jci.co.uk/Carseats2.html
Try the links in the MadSci Library for more information on Physics.