Ohm's Law Formulas for D-C Circuits:
Ohm's Law Formulas for A-C Circuits:
In these formulas is the angle of lead or lag between current and voltage and cos = P/EI = power factor.
Resistors in Series: Rtotal = R1 + R2 + R3 + . . . .
Two Resistors in Parallel:
Resistors in Parallel, General Formula:
Sinusoidal Voltages and Currents:
|Effective value [Also known as Root-Mean Square (RMS) value]||=||0.707 x peak value|
|Half Cycle Average value||=||0.637 x peak value|
|Peak value||=||1.414 x effective value|
|Effective value||=||1.11 x average value|
Resonant Frequency Formulas:
*Where in the second formula f is in kHz and L and C are in microunits.
Q or Figure of Merit:
Voltage/Current Phase Rule of Thumb:
Remember "ELI the ICE man"
ELI: Voltage (E) comes before (leads) current (I) in an inductor (L)
ICE: Current (I) comes before (leads) Voltage (E) in a capacitor (C)