Question

A 5000-km long cable consists of seven copper wires, each of diameter 0.85 mm, bundled together and surrounded by an insulating sheath. Calculate the resistance of the cable. Use 3x10^-6 cm.Ω for the resistivity of the copper.

Answer 1

Answer:

The resistance of the cable is 37762.91 ohms.

Explanation:

let L be the length of the cable, A be the cross-sectional area of the cable and   r be the resistivity of the copper.

then, the resistance of the cable is given by:

R = r×L/A

  = (3×10^-8)×(5000×10^3)/(7×π((0.85×10^-3)/2)^2)

  = 37762.91 ohms

Therefore, the resistance of the cable is 37762.91 ohms.