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?

Input voltage, V1 = 2300 V

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:

V₁/V₂=n1/n2

=> 2300/230 = 4000/n2

=> n2= 4000 x 230 /2300 = 400

Hence, there are 400 turns in the second winding.