Question -
Answer -
Capacitance of thecapacitor, C = 100 μF = 100 × 10−6 F
Resistance of the resistor, R =40 Ω
Supply voltage, V =110 V
Frequency of the supply, ν =12 kHz = 12 × 103 Hz
Angular Frequency, ω =2 πν= 2 × π × 12 × 10303
= 24π × 103 rad/s
Peakvoltage, 
Maximum current, 
For an RC circuit,the voltage lags behind the current by a phase angle of Φ givenas:
Hence, Φ tendsto become zero at high frequencies. At a high frequency, capacitor C acts as aconductor.
In a dc circuit, after the steadystate is achieved, ω = 0. Hence, capacitor C amounts to anopen circuit.