Question

Calculate the resistance of 1 km long copper wire of radius 1 mm resistivity of copper is 1.72*10-8 ohm m

Answer 1

So the calculation part starts,

Length=1 km=1000m

Radius=1 mm=1*10⁻³ m

Resistivity of copper=1.72x10⁻⁸

Resistance=(Resistivity of copper * Length)/(Area)

                  =(Resistivity of copper * Length)/(r²)

Resistance=[1.72*10⁻⁸*1000]/[22/7*(1*10⁻³)²

Resistance=5.5 ohm               

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