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Question
At what voltage is the electric power generated at the generating station? Explain the transmission of this power to your house.
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Solution
At the generating station the electric power is generated at 11,000 volt. This voltage is alternating of frequency 50 Hz. To transmit this power to our house the alternating voltage generated at the generating station is first stepped up from 11,000 V to 1,32,000 V. It is then transmitted to the main sub-station through the high-tension line wires, where it is stepped down to 3,300 V and then transmitted to the city sub-station. At the city sub-station, the voltage is further stepped down to 220 V for supply to the houses through the overhead line wires.
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