EXAMPLE 3.33: Resistance of a metal wire of length 1 m is 26 at 20°C. If the diameter of the
is 0.7 mm, what will be the resistivity of the metal at that temperature?
Answers
Answered by
0
R=26 Ω
l=1m
d−0.3mm
r=
2
d
=
2
0.3×10
−3
=0.15×10
−3
m
A=πr
2
=3.14×(0.15×10
−3
)
2
=0.071×10
−6
m
2
R=
A
ρL
or ρ=
l
RA
=
1
26×0.071×10
−6
=1.84×10
−6
Ωm
Similar questions