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An ideal transformer has a primary voltage of 8 kV and a secondary voltage of 160 V while feeding an 80 kW purely resistive load operating at unity power factor. What are the effective resistive loads seen in the primary and secondary circuits respectively?
- (A) 800 ohm and 1.06 ohm
- (B) 10 ohm and 500 ohm
- (C) 800 ohm and 0.32 ohm
- (D) 1.06 ohm and 500 ohm
Correct answer: (C) 800 ohm and 0.32 ohm
Solution
An ideal transformer conserves power, so each winding delivers/receives the same 80 kW. The equivalent resistance on a side equals V²/P using that side's voltage.
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