A power transmission line feeds input power at 2300 V to a stepdown transformer with its primary windings having 4000 turns.
Question:
A power transmission line feeds input power at 2300 V to a stepdown transformer with its primary windings having 4000 turns. What should be the number of turns in the secondary in order to get output power at 230 V?
Solution:
Input voltage, V1 = 2300
Number of turns in primary coil, n1 = 4000
Output voltage, V2 = 230 V
Number of turns in secondary coil = n2
Voltage is related to the number of turns as:
$\frac{V_{1}}{V_{2}}=\frac{n_{1}}{n_{2}}$
$\frac{2300}{230}=\frac{4000}{n_{2}}$
$n_{2}=\frac{4000 \times 230}{2300}=400$
Hence, there are 400 turns in the second winding.