InterviewSolution
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InterviewSolution
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A coil of number of turns N, area A, is rotated at a constant angular speed omega, in a uniform magnetic field B, and connected to a resistor R. Deduce expressions for : (i) maximum emf induced in the coil, (ii) power dissipated in the coil. |
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Answer» Solution :(i) As SHOWN in Short Answer Question Number 14, induced emf `varepsilon = NBA omega SIN omegat.` `therefore` Maximum emf induced in the coil `varepsilon_(max) = N B A omega` [when `sin omegat = 1]` (ii) Istantaneous power dissipation in the coil Pinsi `P_(inst).= varepsilon_(2)/R = (N^(2)B^(2)A^(2)omega^(2))/R sin^(2)omegat` For one complete cycle mean VALUE of `sin^(2) omegat =1/2`. Hence, the mean value of power dissipation in the coil is given by `P("average") = (N^(2) B^2)A^(2) omega^(2))/R.(1/2)=(N^(2)B^(2)A^(2)omega^(2))/(2R)`. |
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