Calculate the resistance of 2 km long copper wire of radius 2 mm. (Resistivity of copper = 1.72 x 1 0-8)​

Sure, here are the steps to calculate the resistance of a copper wire:

1. First, we need to know the formula for resistance. The formula is R = ρL/A, where R is the resistance, ρ is the resistivity, L is the length of the wire, and A is the cross-sectional area of the wire.

2. We know the resistivity of copper (ρ) is 1.72 x 10^-8 ohm meter.

3. The length of the wire (L) is given as 2 km, which is 2000 meters.

4. The radius of the wire is given as 2 mm, which is 0.002 meters. The cross-sectional area (A) of a wire is given by the formula πr^2, where r is the radius. So, A = π(0.002 m)^2 = 0.00001257 square meters.

5. Now we can substitute these values into the formula for resistance: R = (1.72 x 10^-8 ohm meter * 2000 meters) / 0.00001257 square meters.

6. After calculating, we get the resistance R = 2.74 ohms.

So, the resistance of the 2 km long copper wire of radius 2 mm is approximately 2.74 ohms.