An electric lamp connecvted in series with a variable capacitor and an ac source is glowing with some brightness. Predict your observation when the ac source is replaced by a dc source. How will the brightness of the bulb affectede in each cases if the capacitance of the capacitor is reduced ?

An electric lamp connecvted in series with a variable capacitor and an

1.	An electric lamp connecvted in series with a variable capacitor and an ac source is glowing with some brightness. Predict your observation when the ac source is replaced by a dc source. How will the brightness of the bulb affectede in each cases if the capacitance of the capacitor is reduced ?
Answer» Solution :The bulb will not burn with the dc source beacause the capacitive reactance `X_e=1/C_omega` is infinite. That MEANS the capacitor BLOCKS dc. When the lamp is connected to ac, the bulb will GLOW. On REDUCING the capacitance, capacitative reactance `1/C_omega` will increase. So, the BRIGHTNESS of the bulb gets reduced.

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An electric lamp connecvted in series with a variable capacitor and an ac source is glowing with some brightness. Predict your observation when the ac source is replaced by a dc source. How will the brightness of the bulb affectede in each cases if the capacitance of the capacitor is reduced ?

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