Power Factor (pf):

\[ pf = \frac{Pr}{Pa} = \frac{E \cdot I \cdot \cos \theta}{E \cdot I} = \cos \left(\frac{R}{Z}\right) \]

Where:

• \(pf\) is the power factor.
• \(E\) is the voltage in Volts (V).
• \(I\) is the current in Amperes (A).
• \(Pr\) is the real power in Watts (W).
• \(Pa\) is the apparent power in Watts (W).
• \(R\) is the resistance in Ohms (Ω).
• \(Z\) is the impedance in Ohms (Ω).