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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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