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A toroidal coil has an inductance of 47 mH. Find the maximum self-induced emf in the coil when the current in it is reversed from 15 A to -15 A in 0.01 s. |
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Answer» Data : L = 4.7 × 10-2 H, Ii = 15A, Ii = -15 A, ∆f = 0.01 s The rate of change of current, \(\cfrac{dI}{dt}\) = \(\cfrac {I_f−I_i}{Δt}\) = \(\cfrac{(−15)-15}{0.01}\) = – 3000 A/s ∴ The maximum self-induced emf, e = – L \(\cfrac{dI}{dt}\) (4.7 × 10-2) (- 3000) = 141 V |
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