03-14-2012, 03:39 AM
freeradical wrote:
When a balloon is rubbed with wool, it develops a negative charge. This charge is high enough that it will deflect a stream of water, which is a polar molecule.
If the balloon is attracted to the generator, it has a positive charge. If the balloon is repelled from the generator, the generator is negatively charged.
Yes, but that's relying on the triboelectric series to say the balloon develops a negative charge; if we trust that this end of the series is positive and that end is negative, we could do the same for the generator, right? Unfortunately, we're trying to prove that electrons are negative. It's a fun bit of history, how positive and negative got defined in the Benjamin Franklin era, and sort of gets to the point. How do we prove a flow of electrons in a particular direction?