WAEC - Physics (2024 - No. 38)
Which of the following modes is the most economical method of transmitting electrical power over a long distance?
Alternating current at high voltage and low current.
Alternating current at low voltage and high current.
Direct current at high voltage and low current.
Direct current at low voltage and high current.
Explication
When electricity is transmitted over long distances, power losses occur mainly due to the resistance of the transmission lines. These losses are proportional to the square of the current (I\(^2\)R losses). By using high voltage, the current can be kept low, significantly reducing these losses