Sunday, February 06, 2011
Triboelectricity and enduring mysteries of physics
This past week I hosted Seth Putterman for a physics colloquium here at Rice, and one of the things he talked about is some of his group's work related to triboelectricity, or the generation of charge separation by friction/rubbing. When you think about it, it's quite amazing that we have no first-principles explanation of a phenomenon we're all shown literally as children (rub a balloon on your hair and it builds up enough "static" charge that it will stick to a plaster wall, unless you live in a very humid place like Houston). The amount of charge that may be moved is on the order of 1012 electrons per square cm, and the resulting potential differences can measure in the tens of kilovolts (!), leading to remarkable observations like the generation of x-rays from peeling tape, or UV and x-ray emission from a mercury meniscus moving along a glass surface. In fact, there's still some disagreement about whether the charge moving in some triboelectric experiments is electrons or ions! Wild stuff.
Posted by Douglas Natelson at 9:34 PM