A wire of length 1 m and radius 0.1mm gas a resistance of `100(Omega)`.Find the resistivity of the material .

Explanation

`l = 1m , r = 0.1 xx (10^-3) `
` R = 1000 Omega , f = ?`
` rArr R= rho(l/a) `
` rArr rho = Ra/l`
` =(100 xx 3.14 xx 0.1 xx 0.1 xx (10^-6)/1)`
` = 3.14 xx (10^-6)`
` = pi xx (10^-6) Q-m.`