Physicshard · Past Paper
A transformer is 90% efficient. If it consumes 1000W and the output voltage is 100V, what is the output current?
A10 A
B9 A
C11.1 A
D90 A
✓ Correct Answer: B — 9 A
Output Power = 0.9 * 1000 = 900W. P = VI, so I = 900/100 = 9A.
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