Why do power companies use low currents in power lines when transferring electri
ID: 2017553 • Letter: W
Question
Why do power companies use low currents in power lines when transferring electrical energy over large distances?A.) Because power lines have resistance and resistors transform electrical energy into heat. The lower the current the lower the resistance of the power lines and hence the less electrical energy is lost to heat.
B.) Because power lines have resistance and resistors transform electrical energy into heat. The lower the current, the less heat generated (and hence the less electrical energy lost).
C.) Because power lines have resistance and resistors transform electrical energy into thermal energy. High currents would require larger power lines to reduce the amount of heat loss and hence be much more expensive than the small power lines that low currents require.
D.) Because power lines have resistance and resistors transform electrical energy into thermal energy. According to Ohm's Law, the lower the current the lower the voltage. Thus both the voltage & current will be low and hence the power loss will be small.
Explanation / Answer
_Because power lines have resistance and resistors transform electrical energy into heat. The lower the current, the less heat generated (and hence the less electrical energy lost).