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Question
A wire of uniform thickness with a resistance of 27Ω is cut into three equal pieces and they are joined in parallel. Find the equivalent resistance of the parallel combination.
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Solution
Wire cut into three pieces means new resistance = `27/3` = 9 ohm
Now three resistance connected in parallel :
`1/"R"_"P"=1/"R"_1+1/"R"_2+1/"R"_3=1/9+1/9+1/9`
RP = `9/3` = 3 ohm
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