the resistance of a metal wire of length 1m is 25 ohm at 20 degree celsius
We have,
Length of the metal wire, l = 1 m
Diameter of the wire, d = 0.3 mm
Radius, r = 0.3/2 mm = 0.15 mm = 0.15 x 10–3 m
Resistance of the metal, R = 26 ?