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Questions
A transformer is designed to work from a 240 V a.c. mains and to give a supply of 8 V to ring a house bell. The primary coil has 4800 turns. How many turns will be in the secondary coil?
A transformer is designed to give a supply of 8 V to ring a house-bell from the 240 V a.c. mains. The primary coil has 4800 turns. How many turns will be in the secondary coil?
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Solution
Input ac voltage Vp = 240 V.
Number of turns in primary coil Np = 4800
No. of turns in secondary coil Ns = ?
Output voltage Vs = 8 V.
We know that
`"V"_"p"/"V"_"s" = "N"_"p"/"N"_"s"`
`"N"_"s" = ("N"_"p" xx "V"_"s")/ "V"_"p"`
= `(4800 xx 8) / 240`
= 160
The number of turns in the secondary coil is 160.
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