Answer: Using laminated iron core.
- A Using solid iron core
- B Increasing frequency
- C Using laminated iron core
- D Increasing current
Correct answer: C. Using laminated iron core
Explanation: Eddy currents flow in loops in the core. Laminated core (thin insulated sheets) breaks these paths and reduces eddy current losses.
As a magnet approaches a coil, flux rises steadily and a constant non-zero EMF is induced (Faraday's law). Once the magnet stops moving, flux stays constant and the induced EMF drops to zero - EMF only exists while flux is actively changing.
Concept context
Faraday's and Lenz's laws, motional EMF, self/mutual inductance, eddy currents, and the AC generator - how a changing magnetic flux creates an electric current.