Discuss the uses of eddy current.

(N/A) Eddy currents are loops of electrical current induced within conductors by a changing magnetic field. Despite often being considered a nuisance due to energy loss as heat,they have several practical applications:
$1$. Magnetic Braking: Used in heavy trains and roller coasters. When the magnetic field is applied to the rotating wheels,eddy currents create a magnetic force that opposes the motion,bringing the vehicle to a stop.
$2$. Induction Furnaces: Used to melt metals. $A$ high-frequency alternating current is passed through a coil surrounding the metal,inducing strong eddy currents that generate intense heat,melting the metal.
$3$. Electromagnetic Damping: Used in galvanometers to bring the coil to rest quickly. The eddy currents induced in the metallic frame of the coil create a torque that opposes the motion,providing damping.
$4$. Induction Cooktops: Used for cooking. An alternating magnetic field induces eddy currents in the base of the cooking vessel,which heats up the vessel and the food inside.
$5$. Speedometers: Used to measure the speed of vehicles. $A$ rotating magnet near a metallic drum induces eddy currents,creating a torque that deflects the speedometer needle proportional to the speed.