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Lengths and cross-sectional areas of thr...

Lengths and cross-sectional areas of three copper wires are (l, A ), `(2l, (A)/(2) ) , ((l)/(2) , 2A ) `. Which of these wires has least (minimum) resistance ?

A

wire of cross-sectional are `(A)/(2)`

B

wire of cross-sectional are A

C

wire of cross-sectional area 2A

D

same is all the three cases

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