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ECE 2006 UMD Spring, 2004 Name:____________________ Final Exam: 125 Points (Show work for partial credit) 1. (35 Pts) For the following RLC circuits, calculate the requested quantities: Quantity Value Quantity Value Alpha, Omega, S1, S2 Vc(0) Vc( ) dVc(0)/dt IL(0) IL ( ) dIL(0)/dt Alpha, Omega, S1, S2 Vc(0) Vc( ) dVc(0)/dt IL(0) IL ( ) dIL(0)/dt FIND Vc(t) = Scott Norr Page 1 12/13/2004 ECE 2006 UMD Spring, 2004 2. (30 Pts) Consider the AC voltage waveform shown below: Assuming that Omega, the angular frequency of the waveform is 100 radians per second (ω = 100) and that a current phasor corresponding to the voltage waveform is I = 5 ∠30° Amps, RMS, find the following: a) i(t), the sinusoidal current b) V, the voltage phasor in RMS c) p(t), the instantaneous power d) Plot i(t) on the graph of the sinusoidal voltage e) Plot the voltage and current phasors on the axes provided Scott Norr Page 2 12/13/2004 ECE 2006 UMD Spring, 2004 3. (30 Pts) Analyze the steady state AC circuit below and find the following: a) b) c) d) The reactance X, of the capacitor and each inductor Zeq, the equivalent impedance as seen by the AC voltage source Is, the phasor of the AC current drawn from the source VL, the phasor of the AC voltage across the load resistor Scott Norr Page 3 12/13/2004 ECE 2006 UMD Spring, 2004 4. (30 Pts) For the circuit shown below, find the following: a) The phasor form of the current in each branch b) The average power, P, dissipated by each element c) The reactive power, Q, dissipated by each element c) The average power delivered to the circuit by the source d) The reactive power, Q, delivered by the source e) The complex power, S, delivered by the source Scott Norr Page 4 12/13/2004