Final answer:
The examination method that produces an eddy current is involved in applications like metal detection and magnetic braking, where changes in a magnetic field around a conductor induce currents causing magnetic damping.
Step-by-step explanation:
The examination method that produces an eddy current in the test piece is closely related to applications such as metal detectors, braking systems in trains, and roller coasters. When there is a change in the magnetic field around a conductor, eddy currents are generated within the conductor. This phenomenon creates a magnetic field opposing the motion, which is referred to as magnetic damping. A common demonstration of this effect is a metal pendulum bob swinging between the poles of a magnet; the induced eddy currents quickly damp the motion. In a metal detector, an eddy current is induced in metal close to the detector, altering the induced current in a secondary coil and often signaling the presence of metal.