The wire in the video is 2.0 m long. It’s a 21-gauge wire, meaning that its diameter is 0.723 mm. What is the resistivity of copper, according to your measurements?

The resistance of the copper wire is 0.082 ohm

Explanation:

Given;

length of the wire, L = 2.0 m

diameter of the wire, d = 0.723 mm

radius of the wire, r = d / 2 = 0.3615 mm

resistivity of copper, ρ = 1.68 x 10⁻⁸ ohm m

The area of the copper wire is given by;

A = πr²

A = π (0.3615 x 10⁻³)²

A = 4.106 x 10⁻⁷ m²

The resistance of the copper wire is given by;

Therefore, the resistance of the copper wire is 0.082 ohm

small = small current large mag large current