Transmitting power at high voltage, e.g., 400,000 V, reduces the power loss for transmission lines. But such a voltage would destroy electrical devices in household use. How then can such 400,000 V electricity be used in a normal house?
a. The ground prongs on household plugs reduce the voltage to 120 V.
b. Before reaching households, transformers are used to reduce the voltage appropriately.
c. No matter the incoming voltage, a 120 V device only lets 120 V in.
d. The 400,000 V is just theoretical; long distance transmission lines actually use 120 V.
B
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