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Question
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?
Solution
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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