Question

if the length and radius of a wire is maintained but the material was substituted with another, would the resistance change? why?

Answer 1

The resistance of a material is given by the formula R = ρ*
`(l)/(S)`. Where l is the length and S is the area of the surface calculated with the radius, and ρ is the coefficient that indicates the resistance of a material.

If you keep the lenght and radius, and change the material, ρ will still change and the final resistance (R) will change.