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Electromagnetic brakes, like conventional friction brakes, are responsible for slowing an object, such as a roller coaster. Unlike friction brakes, which apply pressure on two separate objects, electromagnetic brakes slow an object through electromagnetic induction which creates resistance, and in turn either heat or electricity.

Electromagnetic brakes are similar to electrical motors; Non-Ferromagnetic metal discs (rotor) are connected to a rotating coil, a magnetic field between the rotor and the coil creates a resistance used to generate electricity or heat. When electromagnets are used, control of the braking action is made possible by varying the strength of the magnetic field. A braking force is possible when electric current is passed through the electromagnets. Eddy currents result from metal rotating inside the magnetic field. The eddy currents generate the opposite magnetic field of the electromagnets. The opposing fields resist each other and cause a decrease in motion. The resistance of the magnetic fields generates heat which is dissipated through the rotor discs.

Modern roller coasters use this type of braking, but utilize permanent magnets instead of electromagnets. These brakes require no electricity, however, their braking strength cannot be adjusted.

Regenerative braking is not used with brakes of this type because the induction field is used to generate heat, not electricity.

• Sears, Francis Weston; Zemansky, Mark W. (1955). University Physics, 2nd, Reading, MA: Addison-Wesley. 
• Siskind, Charles S. (1963). Electrical Control Systems in Industry. New York: McGraw-Hill, Inc.. ISBN 0-07-057746-3.