Question

calculate the resistance of 1km long copper wire of area of cross section 2×10 power of -2.the resistivity of copper is 1.6×10 power of -8 ohm metre

Answer 1

Length , l = 1 km = 1000m
Area of cross section, A = 2 * 10^(-2) m^2
Resistivity, rho = 1.6 * 10^(-8) ohm m

Resistance = rho l / A = 1.6 * 10(-8) * 10^3 / 2 ^ 10^(-2)
= 8 ^ 10^(-4) ohm

Answer 2

So, this is the answer for your question.
R=0.0008 ohm.
Solution is up there in the pic.
Hope this helped.