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MHT CET 2023 (13 May, Shift 2) · Rotating Conductors & AC Generator

Rotating Conductors & AC Generator question from MHT CET 2023 (13 May, Shift 2)

Q21MHT CET 2023 · 13 MAY · SHIFT 2Easy

Rotating Conductors & AC Generator

A metal disc of radius $R$ rotates with an angular velocity $\omega$ about an axis perpendicular to its plane passing through its centre in a magnetic field of induction $B$ acting perpendicular to the plane of the disc. The magnitude of induced emf between the rim and axis of the disc is

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Answer: (d)

Each radius of the disc behaves like a rod rotating about one end.
$e = \int_0^R B\omega x\,dx = \tfrac{1}{2}B\omega R^2$
So the answer is (d) $\dfrac{BR^2\omega}{2}$ .

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