Q. A copper wire of radius r and length lhas a resistance of R. A second copper wire with radius 2r and length lis taken and the two wires are joined in a parallel combination. The resultant resistance of the parallel combination of the two wires will be
A) 5 R/4
B) 5 R
C) R/5
D) 4 R/5
✔ Correct Answer: R/5
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