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प्रश्न
A power transmission line feeds input power at 2300 V to a stepdown transformer with its primary windings having 4000 turns. What should be the number of turns in the secondary in order to get output power at 230 V?
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उत्तर
Input voltage, V1 = 2300
Number of turns in the primary coil, n1 = 4000
Output voltage, V2 = 230 V
Number of turns in secondary coil = n2
Voltage is related to the number of turns as:
`"V"_1/"V"_2 = "n"_1/"n"_2`
`2300/230 = 4000/"n"_2`
n2 = `(4000 xx 230)/2300` = 400
Hence, there are 400 turns in the second winding.
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संबंधित प्रश्न
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Long distance power transmissions
The large-scale transmission and distribution of electrical energy over long distances is done with the use of transformers. The voltage output of the generator is stepped up. It is then transmitted over long distances to an area sub-station near the consumers. There the voltage is stepped down. It is further stepped down at distributing sub-stations and utility poles before a power supply of 240 V reaches our homes.
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- For a given power level, there is a lower current.
- Lower current implies less power loss.
- Transmission lines can be made thinner.
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