What is the resistance of a 3.1 m length of copper wire 1.7 mm in diameter?

R = ?

L = 3.1 m;

r = 1.7 mm / 2 = 0.85 mm = 0.85 * 10^ (-3) m

Resistivity of copper (rho) = 1.68 * 10 ^ (-8) [Ohm m ]

A = 3.15 * (0.85 * 10^ (-3)) ^2 = 2.26865 * 10 ^ (-6)

R = (Rho) * L / A = 1.68 * 10^ (-8) * 3.1 m / 2.26865 * 10^ (-6) =

= (1.7 * 3.1 / 2.26865) * 10^ (-2) = 0.02323 Ohms (the resistance)