NAEST 2020: Eddy Current and Magnetic Brake Electromagnetism

By Jitender Singh 11-09-2021

Question: NAEST 2020: Eddy Current and Magnetic Brake | Electromagnetism
The video shows a metallic disk rotating about a horizontal axis with the help of an electric circuit. As one pole of a magnet is brought closer to it, it slows down. Choose the correct option(s).

1. Currents are set up in the disk when the pole is brought near it
2. If the magnet is sufficiently strong, the disk can stop.
3. Magnetic forces of Bqv type act on the free electrons of the disk which are in front of the pole brought.
4. Consider the free electrons of the disk close to the pole brought but not in front of it. Magnetic forces of $Bqv$ type act on these electrons.