Rankers Physics

Electromagnetic Induction: Practice Problem & Solution

30. In which of the following devices, the eddy current effect is not used? (2019)
Induction furnace
Magnetic braking in train
Electromagnet
Electric heater

Solution Explained:

To solve this problem, we apply the core principles of Electromagnetic Induction. Understanding the underlying formula is key to arriving at the correct answer below:

Eddy currents are utilized in induction furnaces (for melting metals), magnetic braking in trains, and dead-beat galvanometers.
An electric heater works purely on the principle of Joule heating due to current flowing through a high-resistance wire element.
Therefore, the eddy current effect is not used in an electric heater.

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