Charged Tape, Toy Models, and Dimensionless Parameters

One of the labs we do in the introductory E&M class I’m teaching this term involves investigating charged particles with sticky tape. If you haven’t seen it before, “invisible” tape picks up an electric charge when it’s peeled off a surface quickly, and with a little care, you can create both positively and negatively charged […]

A Brief History of Timekeeping: Final Notes

Between unpleasant work stuff and the Dread Stomach Bug wiping out the better part of five days, I only got my student evaluation comments for my winter term class last week, and I’m only getting around to writing the post-mortem now. This was, for those who may not have been obsessively following my course reports, […]