A coil P is connected to a torch bulb and placed to another coil Q as shown in figure below:


Explain the following observations:


(i) Bulb lights and


(ii) bulb gets dimmer, if the coil P is moves upwards.

(i) The bulb lights due to the mutual induction. The emf is produced in the conductor when the magnetic flux linked with the conductor changes. Due to this emf the bulb gets lighted.


(ii) When the coil P is move upwards the magnetic flux linked with the coil gets decreased due to which the induced emf gets decreased, hence the bulb gets dimmer.


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