# A thin ring of radius R meter has charge q coulomb uniformly spread on it. The ring rotates about its axis with a constant frequency of f revolutions/s. The value of magnetic induction in Wb/m2 at the centre of the ring is?

Here in this case as we know that , the current i will be equal to the product of q and f .

So , I = qf .

$Thereforethemagnitudeofthemagneticinductionatthecentreoftheringis,\phantom{\rule{0ex}{0ex}}B=\frac{{\mu}_{0}I}{2R}=\frac{{\mu}_{0}qf}{2R}$

Hope this helps you .

Regards

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