1. Briefly answer the following questions (56 pts total).
(i) Find I1 and InN in the AC circuit below.
(ii)
(ii) A balanced 3-phase Y-connected source with negative phase sequence has Van=1100o V.
Find Vbn and Vab.
(iii) Consider the balanced 3-phase Y-Y system below, where Van=20030o V, Rw=2 , and
Zp=38 . Find the magnitudes of the line voltage VL and line current IL.
(iv) Given i(t) = 3 A, find the energy stored in the network.
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(v) Assume clockwise mesh currents I1 and I2 for the circuit below. Write two mesh equations.
(vi) Redraw the circuit below with the transformer replaced by its T equivalent. Find Zin.
(vii) Consider the following ideal transformer circuit.
(a) Find the turns ratio. Is this a step-up or step-down transformer?
(b) Find the voltage dropped across ZL.
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2.
(22 pts) In the balanced 3-phase circuit below, Zp = 5010o  and IAB = 420o A. If (+)
phase sequence is assumed, find
(a) IBC;
(b) Vab;
(c) IaA;
(d) the complex power absorbed by each phase of the load;
(e) the total average power delivered by the 3-phase source.
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3. (22 pts) Consider the given ideal transformer circuit and find
(a) I1;
(b) I2;
(c) Sj18;
(d) the total average power supplied by the voltage source.
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