We have a formula for Resistance of a wire R=ρL/A………..implies R is propotional to length. Where ρ, L and A are resistivity, length and the area of conductor respectively. Then R=ρL/πr2……………. ‘ r’ is the radius of cross section Since L and r both are the units of length……one can be expressed in terms of the other i.e. r = nL Then R=ρL/π(nL)2 R=KL/L2…………..k is the constant =ρ/πn2 i.e. R=K/L ie R is inversely propotional to length…which violates the original formula……. Any comments???