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Question
Give the physical significance of self-inductance of a coil.
Solution
When a circuit is switched on, the increasing current induces an emf which opposes the growth of current in a circuit. Likewise, when circuit is broken, the decreasing current induces an emf in the reverse direction. This emf now opposes the decay of current.
(a) Increasing current
(b) Decreasing current
Induced emf ε opposes the changing current i
Thus, the inductance of the coil opposes any change in current and tries to maintain the original state.
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