Question

calculate the resistance of 1 km long copper wire of radius 1mm. Resistivity of copper is 1.72x 10-8Ohm.

Answer 1

given
L=1km=1000m
r=1mm=0.001m
rho=1.72×10^-8
then area(A) = πr²
                =22/7×0.001×0.001
                =0.00000314
                =3.14*10^-6
R =rho×L/A
    =1.72*10^-8×1000/3.14×10^-6
  0n simplifying we get
    =5.5 ohm(approx)

:)hope this ans would help u..

Answer 2

GIVEN THAT

• Length of copper wire = 1 km = 1000 m
• Radius of copper wire = 1 mm = 1 × 10-³ m
• Resistivity of copper = 1.72 x 10⁻⁸

CALCULATION OF RESISTANCE

• (Resistivity of copper × Length)/(Area)
• (Resistivity of copper × Length)/(πr²)
• [1.72×10⁻⁸*1000]/[22/7×(1×10⁻³)²]
• 5.5 ohm