EGR 203 Electric and Electronic Circuits Assignment 9

  1. Given the following circuit, shown below for t < 0. The switch is closed at t = 0. Determine the time constant of the circuit for t > 0.

    VSR1R2R3C
    12 V 4 kΩ80 kΩ 6 kΩ150 μF

  2. A voltage v(t) = 10 cos(2000πt) is applied to each of the following components. Find the complex impedance of each element.
    1. 100-mH inductance
    2. 10-μF capacitance
    3. 100-Ω resistance

  3. Find the complex impedance across terminals a and b if L = 250 mH, C = 20 μF, and R = 300 Ω. Do the calculation for ω = 500 and then repeat for ω = 250 and ω = 1000. Show both cartesian and polar (phasor) forms of the impedance.

  4. Find the complex impedance across the terminals below if L = 250 mH, C = 20 μF, and R = 300 Ω. Do the calculation for ω = 400 and then repeat for ω = 200 and ω = 800. Show both cartesian and polar (phasor) forms of the impedance.

  5. If the current through and the voltage across a component in an electric circuit are i(t) = 17 cos(200π t - π/12) mA
    v(t) = 3.5 cos(200π t - 1.309) V     determine (use the AC form of Ohm's Law and the definitions of impedance)
    1. the complex impedance
    2. whether the component is resistive, inductive, or capacitive. Assume there may be a resistor in series with either a capacitor or an inductor.
    3. the value of the component in ohms and either farads or henries.

Maintained by John Loomis, last updated 8 March 2013