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Mistake Master · AP Physics C: E&M · Unit 13 · Step-Through Animation

The Coil That Hates Surprises

You'll learnwhat an inductor does: it fights any change in its current, and lets a steady current through untouched.

Drive a current through a big coil of wire and try to change it. Turn it up and the coil fights you. Hold it steady and the coil does nothing at all. Turn it down and the coil pushes the current along. Twelve short steps; press Next for each one.

12 STEPS · 5 QUICK CHECKS · FIGHTS THE CHANGE · SILENT WHEN STEADY · v2

fights any change in its current · silent once the current is steady
Before you start
What you're looking at
A big coil of wire. We drive a current through it with a dial, and watch the voltage that appears across the coil.
The question
What does the coil do when its current rises, holds steady, and falls?
Step 1 / 12