These effects are derived from two fundamental observations of physics: a steady current creates a steady magnetic field described by Oersted's law, and a time-varying magnetic field induces an electromotive force in nearby conductors, which is described by Faraday's law of induction.
Butter & salt. Preheat the oven to 400 degrees. Husk the corn, wrap each ear in foil, adding 2 teaspoons of butter to each packet. Bake for about 25 minutes or roast the foil-wrapped corn over hot coals turning once during the cooking. Serve with more butter and salt.
Reserve about 1/2 of the butter. Spread remaining butter on the whole ear of corn. Sprinkle liberally with salt and pepper (I use about 1 teaspoon of each). Bake for 30-45 minutes, until starting to brown. Turn corn occasionally. Remove from oven and spread remaining butter over the top of the corn.