हिंदी

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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प्रश्न

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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उत्तर

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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