NEET 2019 · PhysicsPrevious Year Question
In which of the following devices, the eddy current effect is not used?
Answer: (D) Electric heater. Answer: (d) Solution: Eddy currents (and the heat/force they produce) are used in induction furnaces (heating), magnetic braking (retarding force), and they are deliberately minimised but present in many EM devices.
- A.Induction furnace
- B.Magnetic braking in train
- C.Electromagnet
- D.Electric heater✓
Correct Answer
(D) Electric heater
Solution & Explanation
Answer: (d) Solution: Eddy currents (and the heat/force they produce) are used in induction furnaces (heating), magnetic braking (retarding force), and they are deliberately minimised but present in many EM devices. An electric heater works by ordinary resistive (Joule) heating of a conductor carrying current, NOT by eddy currents. Hence eddy currents are not used in the electric heater → answer D.
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