Pure copper has a resistivity of 1.68 × 10–8 Nm. Some accurate cubes of copper are prepared, and electrical measurements are made, for which current is passed across a pair of opposite faces. a) Comparing a 2.5 cm cube and a 5 cm cube, which will have the higher conductance? Ex- plain your answer. b) Given eight 1 cm cubes, how can they be stacked to get the highest and the lowest resis- tance between opposite faces of the stack? Calculate the resistance of each stack.

Pure copper has a resistivity of 1.68 × 10–8 Nm. Some accurate cubes of copper are prepared, and electrical measurements are made, for which current is passed across a pair of opposite faces. a) Comparing a 2.5 cm cube and a 5 cm cube, which will have the higher conductance? Ex- plain your answer. b) Given eight 1 cm cubes, how can they be stacked to get the highest and the lowest resis- tance between opposite faces of the stack? Calculate the resistance of each stack.