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प्रश्न
A transformer lowers e.m.f. from 220 V to 15 V. If the number of turns in primary are 3520, how many turns are in the secondary coil?
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उत्तर
We know that `"E"_"s"/"E"_"p" = "N"_"s"/"N"_"p"`
or `10/220 = "N"_"s"/3250`
`"N"_"s" = (3520 xx 15)/220 = 240`
Number of turns in secondary are = 240.
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