A transformer has 1000 turns on the primary coil and 20000 turns on the secondary. The primary voltage is 220 V. What is the secondary voltage?
Answer and explanation
Correct answer: B. 4400 V
- Step 1: Vs/Vp = Ns/Np. Step 2. Vs = 220 × (20000 ÷ 1000) = 4400 V. Answer: 4400 V. Why not the others: 11 V is what you get if you invert the turns ratio. 240 V is what you get if you add instead of multiply. 44000 V is what you get if you misplace a power of ten.
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