Question 522Electricity/Electronics - QMED70% to pass
A load is connected across the secondary of the step-up transformer shown in figure "B" of the illustration and the current drawn by the load is 10 amps. If the turns ratio is 1 to 10 and the input voltage is 110 VAC, what will be the current drawn by the primary? Illustration EL-0055
AI Explanation
The correct answer is C) 100 amps.
In a step-up transformer, the turns ratio is inversely proportional to the current ratio. Since the turns ratio is 1 to 10, the current in the primary will be 10 times less than the current in the secondary. With a secondary current of 10 amps, the primary current will be 10 times less, which is 100 amps.
The other options are incorrect because:
A) 1 amp is too low, as the primary current should be 100 times the secondary current.
B) 10 amps is the secondary current, not the primary current.
D) 1000 amps is too high, as the primary current should be 10 times the secondary current.
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