Physics Laws & Theorems
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Faraday's Law of Induction

A changing magnetic flux induces an electromotive force.

Formula

ε=−dΦBdt\varepsilon = -\frac{d\Phi_B}{dt}

Variables

\varepsilonEMF
\Phi_BMagnetic flux
tTime

Example

Moving a magnet through a coil induces a voltage — the basis of every generator.

Did You Know?

Faraday's discovery of induction is why every power plant on Earth generates electricity by spinning magnets.

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