Question

Resistance of a metal wire of length 1m is 26 ohm . If the diameter of the wire is 0.3 mm , what is the resistivity of the metal?

Answer 1

Accepted Answer:

Given:      l = 1 m

                 d = 0.3 mm

                 A = r2 = 3.14 x 2.25 x 10-8 = 7.065 x 10-8m2

Formula:         = R x A / l

                            = 26 x 7.065 x 10-8

                            =183.69 x 10-8m

Thus, the resistivity of the metal wire at 20C is 183.69 x 10-8m.