Question

Two copper wires are of the same length, but one is thicker than the other. Which wire will have more resistance?

Answer 1

We know that,

R = `ρl/A`

Where, ρ = specific resistance

L = length of wire

A =  area of cross-section

let the area of the cross-section of the wires be A₁ & A₂. It is said that one is thicker than the other. 

So A₁ > A₂

When the length of the wire is given to be the same then we can see that `R prop 1/A`.

So, the wire with less area of the cross-section will have more resistance.

Answer 2

The area of the cross-section has an inverse relationship to resistance, so a thinner wire will have more resistance.