Calculating Least Resistance in Copper Wires

Which wire has the least resistance?

Given the lengths and diameters of four copper wires (A, B, C, D), which wire has the least resistance?

The wire with the least resistance is option B (0.50 m length and 2.5 mm diameter).

Resistance is a substance's ability to obstruct the flow of electrical current, symbolized by the capital letter R. The unit of resistance, ohm, is commonly denoted by the Greek letter omega.

To calculate the least resistance, we can determine the L / Area factor for each wire:

For wire A: L / Area factor = 0.50 / π × 0.0005² = 636619.8

For wire B: L / Area factor = 0.50 / π × 0.00125² = 101859

For wire C: L / Area factor = 0.75 / π × 0.0005² = 955414

For wire D: L / Area factor = 0.75 / π × 0.00125² = 152866

Based on the calculations, wire B has the least resistance due to its lower L / Area factor.