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प्रश्न
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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उत्तर
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.
संबंधित प्रश्न
If a bulb of 60W is connected across a source of 220V, find the current drawn by it.
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The diagram above shows a circuit with the key k open. Calculate :
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(iv) the current drawn from the cell when the key k is closed.
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(ii) Why is the deflection produced ?
(iii) What will be the change in the deflection if the magnetic needle is taken just above the conductor AB ?
(iv) Name one device which works on this principle.
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(i) Calculate the resistance of bulb.
(ii) (a) Draw the circuit diagram.
(b) What is the rate of conversion of energy in each bulb?
(c) Total power used by the bulbs.
A bulb is marked 100W, 220V and an electric heater is marked 2000 W, 220 V.
(i) What is the ratio between the resistances of these two devices?
(ii) How does the power-voltage rating of a device help us to decide about the type of leads (connecting wires) to be used for it?
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