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A step-up transformer has 10,000 turns in the secondary coil and 100 turns in the primary coil. An alternating current of 0.5 A flows in...

A step-up transformer has 10,000 turns in the secondary coil and 100 turns in the primary coil. An alternating current of 0.5 A flows in the primary circuit when connected to a 12.0 V a.c. supply.
(a) Calculate the voltage across the secondary coil (b) If the transformer has an efficiency of 90%, what is the current in the secondary coil?

Answers

Mutiso
a) Vs = (Ns / Np) × Vp = (10,000 × 12) / 100 = 1200 V
b) Power in primary = Pp = Ip × Vp= 5.0 × 12 = 60 W
Efficiency = Ps / Pp × 100% but Ps = Is Vs
Is = (60 × 90) / (1200 × 100) = 0.045 A
Mutiso answered the question on October 16, 2018 at 11:06

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