A 1.00 km cable having a cross-sectional area 0.500 cm2 is to be constructed out of equal...

A 1.00 km cable having a cross-sectional area 0.500 cm2 is to be constructed out of equal lengths of copper and aluminum. This could be accomplished either by making a 0.50-km cable of each one and welding them together end to end or by making two parallel 1.00-km cables, one of each metal (below Fig.) Calculate the resistance of the 1.00-km cable for both designs to see which one provides the least resistance.

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