Question

Resistance of a metal wire of length 50 cm is 20 ohm. If the radius of the wire is 0.1 mm, find the resistivity of the material.

Answer 1

Answer:

Given : R=2Ω l=1 m d=0.4 mm =0.0004 m

Cross section area of wire A=

4

πd

2

=

4

π×(0.0004)

2

=1.256×10

−7

m

2

Resistivity of the material ρ=

l

RA

∴ ρ=

1

2×1.256×10

−7

=2.514×10

−7

Ωm

I hope this answer is i