Basic AC Circuit Formulas

Basics:

\(v=V_m\sin{\omega t}\)v = value of alternating voltage at time t (called instantaneous value)
Vm = maximum value of alternating voltage
\(\omega\)= Angular velocity of the coil
\(i=I_m\sin{\omega t}\)i =value of alternating current at time t (called instantaneous value)
Im = maximum value of alternating current
\(\omega\) = Angular velocity of the coil
\(T=\frac{1}{f}\)T = Time period in second
f = frequency in Hz
\(\omega={2 \pi f}\)\(\omega\)= Angular frequency
f = frequency
\(I_{av}=\frac{2 I_m}{\pi} =0.637I_m \)

\(V_{av}=\frac{2 V_m}{\pi}=0.637V_m\)
Iav = Average value of Current
Im= Maximum value of Current
\(I_{rms}=\frac{ I_m}{\sqrt{2}} =0.707I_m \)

\(V_{rms}=\frac{ V_m}{\sqrt{2}}=0.707V_m\)
Irms = RMS value of Current
Im= Maximum value of Current
\(\text{Form factor}= \frac{\text{rms value}}{\text{average value}}\)For an alternating voltage or current varying sinusoidally, its value is 1.11
\(\text{Peak factor or Crest Factor}= \frac{\text{maximum value}}{\text{rms value}}\)For an alternating voltage or current varying sinusoidally, its value is 1.414
\(X_{L}={2\pi f L}={\omega L} \)XL=Inductive Reactance
f= frequency
L= Inductance
\(X_{C}=\frac{ 1}{2\pi f C}= \frac{ 1}{ \omega C}\)XC=Capacitive Reactance
f= frequency
C= Capacitance

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