A balanced Y–Y connected three-phase circuit has line-to-line rms voltage 208 V. The load absorbs total power 432 W at power factor 0.6 leading. Its per-phase impedance Z is approximately
For a star load, $V_{ph}=208/\sqrt3$ V. From $P=3V_{ph}^2\cos\phi/|Z|$, obtain $|Z|=208^2(0.6)/432=60.09$ Ω.
The angle magnitude is arccos(0.6)=53.13°. Leading current means a capacitive, negative impedance angle. Hence **$Z\approx60\angle-53.1^\circ\ \Omega$, C**.
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