Physics-
General
Easy
Question
In figure, the switch S is closed so that a current flows in the iron-core inductor which has inductance L and the resistance R. When the switch is opened, a spark is obtained in it at the contacts. The spark is due to
- a slow flux change in L
- a sudden increase in the emf of the battery B
- a rapid flux change in L
- a rapid flux change in R
The correct answer is: a rapid flux change in L
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