Impedance in RL Circuits

Impedance is the resultant of phasor addition of R and X_L.

The symbol for impedance is Z.

Impedance is the total opposition to the flow of current and is expressed in ohms.

The below Equation is the mathematical representation of the impedance in an RL circuit.

Example:

If a 100 Ω resistor and a 60 Ω X_L are in series with a 115V applied voltage (Figure 6), what is the circuit impedance?

Figure 6 : Simple R-L Circuit

Solution:

Z = √ (100² + 60²)

Z = √ 13600

Z = 116.6 Ω