A. NILAI EFEKTIF
| Tegangan | Arus | |
|---|---|---|
| Nilai Sesaat | \(V = V_{\text{max}} \:.\: \sin \omega t\) | \(I = I_{\text{max}} \:.\: \sin \omega t\) |
| Nilai Efektif | \(V_{\text{eff}} = \dfrac {V_{\text{max}}}{\sqrt{2}}\) | \(I_{\text{eff}} = \dfrac {I_{\text{max}}}{\sqrt{2}}\) |
| Nilai Rata-rata | \(V_{\text{rata-rata}} = \dfrac {2 \:.\: V_{\text{max}}}{\pi}\) | \(I_{\text{rata-rata}} = \dfrac {2 \:.\: I_{\text{max}}}{\pi}\) |
B. RESISTOR, INDUKTOR DAN KAPASITOR
Resistor
\(V = I \:.\: R\)
\(V\) dan \(I\) sefase.
\(V = V_{\text{max}} \sin \omega t\)
\(I = I_{\text{max}} \sin \omega t\)
Induktor
\(V = I \:.\: X_L\)
\(X_L = \omega \:.\: L\)
\(V\) mendahului \(I\).
\(V = V_{\text{max}} \sin \omega t\)
\(I = I_{\text{max}} \sin (\omega t - 90)\)
\(V = V_{\text{max}} \sin (\omega t + 90)\)
\(I = I_{\text{max}} \sin \omega t\)
Kapasitor
\(V = I \:.\: X_C\)
\(X_L = \dfrac {1}{\omega \:.\: C}\)
\(I\) mendahului \(V\).
\(V = V_{\text{max}} \sin \omega t\)
\(I = I_{\text{max}} \sin (\omega t + 90)\)
\(V = V_{\text{max}} \sin (\omega t - 90)\)
\(I = I_{\text{max}} \sin \omega t\)
C. RANGKAIAN RLC
Impedansi
\(Z = \sqrt{R^2 + (X_L - X_C)^2}\)
Tegangan dan kuat arus
\(V = I \:.\: Z\)
\(V_R = I \:.\: R\)
\(V_L = I \:.\: X_L\)
\(V_C = I \:.\: X_C\)
\(V = \sqrt{V_R^2 + (V_L - V_C)^2}\)
Beda fase tegangan dan arus
\(\tan \theta = \dfrac {X_L - X_C}{R}\)
\(\tan \theta = \dfrac {V_L - V_C}{V_R}\)
Daya
\(P_{\text{eff}} = V_{\text{eff}} \:.\: I_{\text{eff}} \:.\: \cos \theta\)
\(P_{\text{eff}} = I_{\text{eff}}^2 \:.\: R\)
Faktor daya
\(\cos \theta = \dfrac {R}{Z} = \dfrac {V_R}{V}\)
Resonansi
Resonansi terjadi saat reaktansi induktif \(X_L\) sama besar dengan reaktansi kapasitif \(X_C\).
\(X_L = X_C\)
Frekuensi resonansi
\begin{equation*} \begin{split} X_L & = X_C \\\\ \omega \:.\: L & = \frac {1}{\omega \:.\: C} \\\\ \omega^2 & = \frac {1}{LC} \\\\ \omega & = \sqrt{\frac {1}{LC}} \\\\ 2 \pi \:.\: f & = \frac {1}{\sqrt{LC}} \\\\ f & = \frac {1}{2 \pi \sqrt{LC}} \end{split} \end{equation*}
Saat terjadi resonansi, nilai impedanzi \(Z\) mencapai minimum dan kuat arus \(I\) mencapai maksimum.