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Tuesday, 10 March 2026
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The primary coil of a transformer has N turns and is connected to a 120 V a.c. power ...

The primary coil of a transformer has N turns and is connected to a 120 V a.c. power line. If the secondary coils has 1 000 turns and a terminal voltage of 1 200 volts, what is the value of N?
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  • A 120
  • B 100
  • C 1 000
  • D 1 200
Correct Answer: Option B
Explanation:
For the transformer, V ∝ ∩
=> V s ∝ ∩s; Vp ∝ ʌp
=> Vp/Vv = ∩p/∩s, therefore 120/1200 = ∩p/1000
therefore ∩p * 1200 = 120 * 1000
∩p = 120*1000/1200 = 100

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