The effect in which a suddenly magnetized iron bar
The effect in which a suddenly magnetized iron bar rotates in the opposite direction of an applied current is named after de Haas and this man. This man introduced the idea of stimulated emission while proving Planck's radiation equation. He also developed the equivalence principle and postulated that the speed of light is the same in all reference frames, and his paper "On the Electrodynamics of Moving Bodies" introduced special relativity. For 10 points, name this man who won the 1921 Nobel Prize in Physics for his explanation of the photoelectric effect.
The effect in which a suddenly magnetized iron bar rotates in the opposite direction of an applied current is named after de Haas and this man.