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प्रश्न
A coil Q is connected to low voltage bulb B and placed near another coil P as shown in the figure. Give reasons to explain the following observations:
(a) The bulb ‘B’ lights
(b) Bulb gets dimmer if the coil Q is moved towards left.
उत्तर
(a) The A.C. source creates a varying magnetic field in coil P. This varying magnetic field of P is linked to coil Q. Hence, an induced current is produced in Q, which lights bulb B.
(b) As coil Q moves away from P, the rate of variation of magnetic flux changes. Therefore, the induced e.m.f. inside coil Q decreases and bulb B gets dimmer.
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