An average induced e.m.f. of $ 1 \mathrm{~V} $ appears in a coil when the current in it is changed from $ 10 \mathrm{~A} $ in one direction to $ 10 \mathrm{~A} $ in opposite direction in $ 0.5 \mathrm{~s} $. Self-inductance of the coil is

Question

An average induced e.m.f. of $ 1 \mathrm{~V} $ appears in a coil when the current in it is changed from $ 10 \mathrm{~A} $ in one direction to $ 10 \mathrm{~A} $ in opposite direction in $ 0.5 \mathrm{~s} $. Self-inductance of the coil is, $ 25 \mathrm{mH} $, $ 50 \mathrm{mH} $, $ 75 \mathrm{mH} $, $ 100 \mathrm{mH} $

MARKS App · Accepted Answer

From Faraday's law of electromagnetic induction, magnitude of average induced emf is given by, ε = - L ∆ i ∆ t , where L , i & t represents coefficient of self inductance, current and time respectively. On substituting corresponding parameters in above relation, we have ⇒ 1 = - L 10 - ( - 10 ) 0 . 5 ⇒ L = 1 × 0 . 5 20 = 1 40 = 0 . 025 H = 25 mH

Search any question & find its solution

Looking for more such questions to practice?