Computer Science I / Magnetism and Electromagnetism
Practice question · True or false

A strong magnet placed beside a coil and left stationary induces a steady current in the coil.

Hints
  1. Faraday's law is about a rate of change.
  2. A constant flux has zero rate of change.
Show the answer

False

Why

False. Induced EMF is dΦ/dt-d\Phi/dt, so a constant flux, however large, induces nothing. Current flows only while the magnet moves, the coil moves, or the field changes. This is why generators must rotate and why transformers work on alternating current and pass no direct current at all.

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