Question

Calculate the resistance of 1km long wire of radius 1mm.If the resistivity of wire is 1.72 ×10ki power 8 ohm

Answer 1

Here l=1000m;r=1mm;rho=1.72*10^8ohm on putting the value on the formula i.e R=rho*l/A and area of cross section equals to 3.14 we get the answer that is 1.72*10^8 *1000/3.14