Multiple Choice
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.
Correct Answer:

Verified
Correct Answer:
Verified
Q17: A 50-Ω resistor,a 0.1-H inductor,and a 20-µF
Q18: Consider an AC series circuit containing a
Q20: What is the magnitude of the phase
Q22: An AC series circuit contains a resistor
Q24: An AC voltage source,with a peak output
Q25: An AC power generator produces 100 A
Q44: The output voltage of an AC generator
Q68: In some countries the AC frequency is
Q95: In an RL circuit,which of the following
Q106: What is the impedance of an AC