For 10 points, name this law of electromagnetism that says that an induced current will produce a magnetic field to oppose the induced change in magnetic flux through the circuit.
It explains why a switch will sometimes spark when turned on but not off. It is the reasoning behind older mass balances placing a sheet of aluminum between the poles of a magnet, and on the molecular level, it explains diamagnetism. Also the reason that transformers can overheat with direct current, it describes why pushing a bar magnet through a conducting loop gets tougher as the magnet approaches. For 10 points, name this law of electromagnetism that says that an induced current will produce a magnetic field to oppose the induced change in magnetic flux through the circuit.
It explains why a switch will sometimes spark when turned on but not off.
{Lenz}'s Law