Q8 of 45 Page 301

In the arrangement shown in the figure, there are two coils wound on anon-conducting cylindrical rod. Initially the key is not inserted. Then the key is inserted and later removed. Then, which of the following statement is correct?

a. The deflection in the galvanometer remains zero throughout.


b. There is a momentary deflection in the galvanometer but it dies out shortly.



b


Explanation: When the key is inserted, an electric current flows through coil 1 which produces a magnetic field. This change in the magnetic field (from zero) induces an emf in coil 2 due to electromagnetic induction.But as the key is removed no magnetic field is produced and the emf in coil 2 turns zero.



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