Three copper wires of lengths and cross sectional areas are $(l,\,A),\,(2l,\,A/2)$ and $(l/2,\, 2A)$ . Resistance is minimum in
  • Awire of cross-sectional area $A/2$
  • Bwire of cross-sectional area $A$
  • Cwire of cross-sectional area $2A$
  • D
    same in all the three cases
AIIMS 2013,AIPMT 1997, Easy
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