The resistance of a copper wire if it’s length is 1 m and its diameter is 2 mm is
A. 5.4 X 10^-3Ω
B. 5Ω
C. 4Ω
D. 2Ω
Answers
Answer:
length=1m
diameter=2mm
change it in meter I.e. 2÷1000=0.002m
resistivity of cu =1.72×10^-8
R(RESISTANCE)=RHO(P)×LENGTH÷area
area=pie×r^2
R=1.72×10^-8×1×7÷22×0.002×0.002
=2 ohm is right ans. option (d=)hope....it will help u
Given,
Length of the copper wire = 1 m
Diameter of the copper wire = 2 mm
To Find,
The resistance of the copper wire.
Solution,
The formula for calculating the resistance of a wire is
R = ρL/A
Where l is the length of the wire and A is the area of the wire.
Radius = Diameter/2 = 2/2 = 1*10⁻³ m
Area = πr² = 22/7(1)*10⁻⁶
Resistivity of copper = 1.72×10^-8 Ωm
Resistance = 1.72×10^-8*1/( 22/7(1)*10⁻⁶)
Resistance = 200*10⁻²
Resisatnce = 2 Ω
Hence, the correct answer is option (d) 2 Ω.
Given,
Length of the copper wire = 1 m
Diameter of the copper wire = 2 mm
To Find,
The resistance of the copper wire.
Solution,
The formula for calculating the resistance of wire is
R = ρL/A
Where l is the length of the wire and A is the area of the wire.
Radius = Diameter/2 = 2/2 = 1*10⁻³ m
Area = πr² = 22/7(1)*10⁻⁶
Resistivity of copper = 1.72×10^-8 Ωm
Resistance = 1.72×10^-8*1/( 22/7(1)*10⁻⁶)
Resistance = 200*10⁻²
Resisatnce = 2 Ω
Hence, the correct answer is option (d) 2 Ω.