Which listed device does NOT use eddy-current effects?

Question

G1 Physics · Accepted Answer

Step 1: Eddy currents are useful for magnetic braking, induction heating and induction furnaces. Step 2: The ordinary electromagnet works by current in a wound coil; bulk induced circulating currents are not needed for its intended field. Step 3: Therefore the device not using the eddy-current effect is an electromagnet. Answer B. Final answer: (B) Electromagnet.