# 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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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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