An inductor L of inductance XL is connected in series with a bulb B and an ac source. How would brightness of the bulb change when (i) number of turns in the inductor is reduced, (ii) an iron rod is inserted in the inductor and (iii) a capacitor of reactance $X_C = X_L$ is inserted in series in the circuit. Justify your answer in each case.
CBSE DELHI - SET 2 2015
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- Increases
As number of turns decreases, L decreases, hence current through bulb increases. /voltage across bulb increases.
- Decreases
- Increases
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