Question

Calculate the resistance of a 1km long aluminium wire of diameter 5mm. Find resistance of the wire made of nichrome of same length and diameter also. (Resistivity of aluminium is 28×10-8 Ωm; Resistivity of nichrome is 100×10-6 Ωm)

Answer 1

Answer:

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 

Step-by-step explanation done