Scientists at Northwestern University may have figured out why walking on carpet in your socks, petting your furry friend, or rubbing a balloon on your hair creates static electricity. In a new study, they say they’ve found that rubbing can create tiny deformations on an object’s surface that allows the phenomenon to occur. People have known about the existence of static electricity for millennia, with the first recorded observation of it thought to have been made by Greek philosopher Thales of Mileus in 600 B.
C. (Thales noticed that fur would attract dust right after it was rubbed with amber). Since then, we’ve learned that lots of things can cause static electricity and that it can be advantageous to animals, such as ticks that use static electricity to extend their host-grappling range .
But scientists have remained in the dark about many of the basics behind static electricity, particularly why rubbing often induces it—at least, perhaps, until now. “For the first time, we are able to explain a mystery that nobody could before: why rubbing matters,” said lead researcher Laurence Marks, Professor Emeritus of Materials Science and Engineering at Northwestern, in a statement from the university. “People have tried, but they could not explain experimental results without making assumptions that were not justified or justifiable.
We now can, and the answer is surprisingly simple.” Most people have seen the classic balloon trick, in which rubbing a balloon on you.
