A power transmission line feeds input power at 2200 V to a step down transformer with its primary windings having 4000 turns. The number of turns in the secondary in order to get output power at 220 V will be:

400

The correct answer is Option (2) → 400

Using transformer equation,

$\frac{V_1}{V_2}=\frac{N_1}{N_2}$

$⇒N_2=\frac{N_1V_2}{V_1}=\frac{220×4000}{2200}=400\,turns$