Question
What is a capacitive and an inductive AC circuit? Explain.
✓
Answer
→Amplitude of electric current in an $L - C - R$ AC series circuit (Amplitude means maximum current)
$i_m=\frac{u_m}{\sqrt{ R ^2+\left( X _{ C }- X _{ L }\right)^2}}$
→Phase difference between voltage and current
$\phi=\tan ^{-1}\left(\frac{ X _{ C }- X _{ L }}{ R }\right)$
→Case-I : If $X _{ C }> X _{ L }$ phase difference $\phi$ is positive. and the circuit is predominatly capacitive. Consequently, the current in the circuit leads the source voltage.
→Case-II : If $X _{ C }< X _{ L }, \phi$ is negative and the circuit is predominantly inductive. Consequently, the current in the circuit lags the source voltage.
→Figure shows the phasor diagram and variation of $v$ and $i$ with $\omega t$ for the case $X _{ C }> X _{ L }$.
$i_m=\frac{u_m}{\sqrt{ R ^2+\left( X _{ C }- X _{ L }\right)^2}}$
→Phase difference between voltage and current
$\phi=\tan ^{-1}\left(\frac{ X _{ C }- X _{ L }}{ R }\right)$
→Case-I : If $X _{ C }> X _{ L }$ phase difference $\phi$ is positive. and the circuit is predominatly capacitive. Consequently, the current in the circuit leads the source voltage.
→Case-II : If $X _{ C }< X _{ L }, \phi$ is negative and the circuit is predominantly inductive. Consequently, the current in the circuit lags the source voltage.
→Figure shows the phasor diagram and variation of $v$ and $i$ with $\omega t$ for the case $X _{ C }> X _{ L }$.
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