EARTH SCIENCE
MAGNETISM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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transmits alternating current at high voltages, but is used at low voltages
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transmits direct current at high voltages, but is used at low voltages
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transmits alternating current at low voltages, but used at high voltages
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transmits direct current at low voltages, but used at high voltages
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Detailed explanation-1: -The primary reason that power is transmitted at high voltages is to increase efficiency. As electricity is transmitted over long distances, there are inherent energy losses along the way. High voltage transmission minimizes the amount of power lost as electricity flows from one location to the next.
Detailed explanation-2: -Electricity is transmitted at high voltages to reduce the energy loss that occurs over long distances. Power is usually transmitted through overhead power lines.
Detailed explanation-3: -Alternating current (AC) is the type of electric current generated by the vast majority of power plants and used by most power distribution systems. Alternating current is cheaper to generate and has fewer energy losses than direct current when transmitting electricity over long distances.
Detailed explanation-4: -For constant electric power, higher the voltage, lower is the current (as P=IV) through the wire. As power loss due to Joule’s heating is proportional to I2, for a small current, power loss is also small. So, power is transmitted over long distances at high voltage to minimize power loses due to Joule’s heating.