Question

How does a magnetic brake work? From a physics stand point

Answer 1

Magnetic braking works because of induced currents and Lenz’s law. If you attach a metal plate to the end of a pendulum and let it swing, its speed will greatly decrease when it passes between the poles of a magnet. When the plate enters the magnetic field, an electric field is induced in metal and circulating eddy currents are generated. These currents act to oppose the change in flux through the plate, in accordance with Lenz’s Law. The currents, in turn, heat the plate, thereby reducing its kinetic energy. As a result, brake occurs.