What is the resistance of : a) a 1.70 m long copper wire that is 0.700 mm in diameter? b) a 20.0 cm long piece of carbon with a 2.00 mm x 2.00 mm square cross section?

(I). The resistance of the copper wire is 0.0742 Ω.

(II). The resistance of the carbon piece is 1.75 Ω.

Explanation:

Given that,

Length of copper wire = 1.70 m

Diameter = 0.700 mm

Length of carbon piece = 20.0 cm

Cross section area

(I). We need to calculate the area of copper wire

Using formula of area

We need to calculate the resistance

Using formula of resistance

Put the value into the formula

(II). We need to calculate the resistance

Using formula of resistance

Put the value into the formula

Hence, (I). The resistance of the copper wire is 0.0742 Ω.

(II). The resistance of the carbon piece is 1.75 Ω.