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Question
A moving coil galvanometer of resistance 55 Ω produces a full scale deflection for a current of 250 mA. How will you convert it into an ammeter with a range of 0 - 3A?
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Solution
Galvanometer - Ammeter
and shunt is parallel to galvanometer
Rs(I - ig) = igG
`"R"_"s" = (250 xx 10^-3 xx 55)/(3 - 250 xx 10^-3)`
`"R"_"s" = 13.75/2.75`
Rs = 5 Ω
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