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How does wire length affect electrical resistance?

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The electrical resistance of a wire is directly proportional to its length. This means that as the length of a wire increases, its resistance to the flow of electric charge also increases.12

This relationship is defined by the formula for resistance:
$R = ρ \frac{l}{A}$

In this equation:
* $R$ is the resistance in ohms.
* $ρ$ (rho) is the resistivity of the material, which is a characteristic property of the substance used.32
* $l$ is the length of the wire.32
* $A$ is the cross-sectional area of the wire.32

Because resistance is directly proportional to length, a longer wire provides more opposition to the movement of charge carriers, resulting in higher resistance compared to a shorter wire of the same material and cross-sectional area. Conversely, a larger cross-sectional area results in lower resistance.12