Consider a rotating disk on a uniform magnetic field. Faraday's law states that(adsbygoogle = window.adsbygoogle || []).push({});

[tex] \epsilon = - \frac{d\phi}{dt}[/tex]

In this situation, [tex]\vec B[/tex] is constant and the area of the disk is constant. Hence, the magnetic flux is constant and there should be no emf. What am I missing?

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# Faraday's Disk Dynamo: why is there an emf?

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