Calculate the resistivity of the material of wire 1.0 metre long 0.4 millimetre diameter and having a resistance of 2.0
Answers
Answer:
Here is your Answer
Explanation:
Solution :
Here, l=1.0m ,
D=0.4mm=0.4×10−3m,R=2.0Ω
ρ=RAl=RπD24l=2.0×(22/7)(0.4×10−3)24×1.0
=2.51×10−7Ωm
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
Answer:
Resistivity = 2.4 × 10^-8 Ohm-metre
Explanation:
Length = 10m
Area = we have given diameter so for radius , D/2 = 0.4mm/2=0.2mm
so area = Pie×(0.2×10^-3)^2
= 3.14 × 0.04 × 10^-6
= 0.1256 × 10^-6
area = 1.2 × 10^-7
Now we know ,
Resistance = Resistivity x Lenght/area
Resistivity = Resistance x area/ length
= 2 × 1.2 × 10^-7/10m
= 2.4 × 10^-8
Resistivity = 2.4 × 10^-8 Ohm-metre