Entries by vanhees71

The Homopolar Generator: An Analytical Example

Introduction It is surprising that the homopolar generator, invented in one of Faraday’s ingenious experiments in 1831, still seems to create confusion in the teaching of classical electrodynamics. This is the more surprising as the problem of the “electromagnetism of moving bodies” has been solved more than 100 years ago by Einstein in his famous…

Some Sins in Physics Didactics

Introduction There are many sins in physics didactics. Usually they occur, because teachers, professors, textbook or popular-science-book writers, etc. try to simplify things more than possible without introducing errors in reasoning, or they copy old-fashioned methods of explaining an issue, leading to the necessity to “erase” from the students’ heads what was hammered in in…