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A solenoid has L = 2 H. Current decreases from 5 A to 1 A in 0.1 s. EMF induced:
A80 V
B40 V
C20 V
D8 V
Answer & Solution
Correct answer: A. 80 V
|ε| = L × |dI/dt| = 2 × (4/0.1) = 80 V. Sign indicates EMF opposes decrease (i.e., tries to maintain current).
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