A power transmission line feeds input power at 2300 V to a step-down 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?

1. 200
2. 250
3. 350
4. 400

 A small town with a demand of 800 kW of electric power at 220 V is situated 15 km away from an electric plant generating power at 440 V. The resistance of the two wirelines carrying power is 0.5 $\Omega$ per km. The town gets power from the line through a 4000-220 V step-down transformer at a sub-station in the town. The transformer rating is:

1. 440−7000 V
2. 4000−20 V
3. 500−6500 V
4. 220−1100 V