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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 increases

Text Solution

Verified by Experts

The correct Answer is:
B
Current `(I) =V/Z=V/(sqrt(R^2+X_C^2))`
`implies I=V/(sqrt(R^2+1/(omega^2C^2)))`
As `omega` increase, current increase and bulb glows brighter.
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