100 likes | 587 Views
Impedance and Reactance. Resistance. Inductance. Capacitance. In general,. Z = Impedance. Definitions for Impedance. Impedance in the frequency domain is analogous to resistance, capacitance, and inductance in the time domain The imaginary part of the impedance is called the “Reactance”
E N D
Impedance and Reactance Resistance Inductance Capacitance In general, Z = Impedance ECE 201 Circuit Theory I
Definitions for Impedance • Impedance in the frequency domain is analogous to resistance, capacitance, and inductance in the time domain • The imaginary part of the impedance is called the “Reactance” • The units of Impedance and Reactance are Ohms ECE 201 Circuit Theory I
Circuit Element Resistance Inductance Capacitance Impedance Reactance R -------------- jωL ωL j(-1/ωC) -1/ωC Impedance and Reactance Values ECE 201 Circuit Theory I
Assessment Problem #9.3 • The current in a 20 mH inductor is 10cos(10,000t+30)mA. • Calculate the inductive reactance • ωL = (10,000)(20X10-3) = 200 Ω • Calculate the impedance of the inductor • jωL = j200 Ω • Calculate the phasor voltage V • V = (20090)(10X10-330) = 2(120) ECE 201 Circuit Theory I
Assessment Problem #9.3 (continued) • Calculate the steady-state expression for the inductor voltage v(t) • v(t) = 2cos(10,000t+120) volts ECE 201 Circuit Theory I