Question 218 of 276

A small bar magnet is moved through a coil at constant speed from one end to the other. Which of the following series of observations will be seen on the galvanometer $\text{G}$ attached across the coil?
Three positions shown describe: (a) the magnet's entry (b) magnet is completely inside and (c) magnet's exit.

ABCD

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Answer: (B)

(a) When the bar magnet entering the coil the magnetic flux link with the coil increases, and according to the Faraday's law of electromagnetic induction, the emf will induce in the coil, which in tern induces current and galvanometer shows the deflection towards right.
(b) When the bar magnet is inside the coil no change in magnetic flux link with the coil, therefore galvanometer do not show deflection.
(c) When the bar magnet exit from the coil the magnetic flux link with the coil decreases, and according to the Faraday's law of electromagnetic induction, the emf will induce in the coil, in opposite direction which in tern induces current and galvanometer shows the deflection towards left.