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Question
A transformer lowers e.m.f. 220 V to 12 volts. If the number of turns in primary are 8800, how many turns are in secondary coil?
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Solution
Using `"E"_"p"/"E"_"s" = "N"_"p"/"N"_"s"`
∴ `"200 V"/"12 V" = 8800/"N"_"s"`
∴ `"N"_"s" = (8800 xx 12)/220 = 40 xx 12 = 480`
∴ Number of turns in secondary coil = 480.
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