Question

determine the resistance of a copper wire having a length of 1 km and diameter of 0.5mm.plzz explain this sum to me with detail calculations No Shortcuts at all

Answer 1

Resistance= specific Resistivity X length / Area of cross section

Given, Specific Resistivity of Cu= 1.72 x 10^-8 ohm m
Length = 1 km= 1000m
Diameter = 0.5 mm = 0.0005m

Area= π(0.00025)²
= 6.25π × 10 ^-8

Resistance= (1.72×10^-8) × (1000)/( 6.25π×10^-8)
= 87.5 ohm