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In a uniform magnetic field of induction B, a wire, in the form of semicircular of radius ‘R’, rotates about the diameter of the circle with an angular speed 'ω' . The axis of rotation is perpendicular to the field. If the total resistance of the circuit is R’, the near power generated per period of rotation is (1) \(\frac{B\pi R^2 ω}{2R'}\) (2) \(\frac{(B\pi R^2 ω)^2}{8R'}\) (3) \(\frac{(B\pi Rω)^2}{8R'}\) (4) \(\frac{B\pi R^2ω^2}{8R'}\)

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