Question

Resistance of a metal wire of length 5 m is 100 Ω . If the area of cross - section of the wire is `3 × 10^-7  "m"^2` , Calculate the resistivity of the metal . 

Answer 1

R = 100 Ω

l = 5m

`A = 3 xx 10^-7  "m"^2`

`K = (rho l)/A` ⇒ `therefore rho = (RA)/l`

`δ = (100 xx 3 xx 10^-7)/5 = 60 xx 10^-7`

                                          = `6 xx 10^-6   Omega-m`