Question 248Electricity & Electronics - Assistant Engineer

70% to pass

The turns ratio of the tapped step-down transformer shown in figure "C" of the illustration is four to one and all taps are equally spaced. If 440 volts were applied between 'H1' and 'H4', what would appear across 'X1' and 'X4'? Illustration EL-0082

Diagram for USCG Electrical Assistant: The turns ratio of the tapped step-down transformer shown in figure "C" of the...
A110 volts
B220 volts
C440 volts
D1760 volts
AI Explanation

The correct answer is A) 110 volts. In a tapped step-down transformer, the turns ratio determines the voltage ratio between the primary and secondary windings. Since the turns ratio is 4:1, this means that for every 4 turns on the primary winding, there is 1 turn on the secondary winding. Therefore, if 440 volts are applied to the primary (H1 to H4), the voltage that will appear across the secondary (X1 to X4) will be 440 volts divided by the turns ratio of 4, which equals 110 volts. The other options are incorrect because B) 220 volts would be the result if the turns ratio was 2:1, C) 440 volts would be the primary voltage, and D) 1760 volts does not align with the given 4:1 turns ratio.

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