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An AC voltage source of variable angular...

An `AC` voltage source of variable angular frequency `omega` and fixed amplitude `V_(0)` is connected in series with a capacitance `C` and an electric bulb of resistance `R` (inductance Zero). When `omega` is increase.

A

the bulb glows dimmer

B

the bulb glows brighter.

C

total impedance of the circuit is unchanged

D

total impedance of the circuit increase.

Text Solution

Verified by Experts

The correct Answer is:
B
(b) When capacitor is connected in series with the resistor then impedance of the circuit is given by the following relation :
`Z = sqrt(R^(2)+(1)/(omega^(2)C^(2)))`
Hence when angular frequency is increased then impedance of the circuit is decreased. Due to decrease in imedance current flowing in the circuit increases and hence bulb glows brighter. Option ( b) corrcet.
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