Britannica Sources used in this answer

How does increasing the length of a wire affect its electrical resistance?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Conductors and insulators in flexible electronics — electronics The development of screen-printable electronic ink for flexible electronics.

In electrical engineering, the resistance of a wire is directly proportional to its length. This means that as you increase the length of a wire, its electrical resistance increases proportionally.12

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

Where:
* $R$ is the resistance in ohms.
* $ρ$ (rho) is the resistivity of the material.
* $l$ is the length of the wire.
* $A$ is the cross-sectional area of the wire.

Because the length ( $l$ ) is in the numerator of this equation, a longer wire provides more resistance to the flow of charge compared to a shorter wire of the same material and cross-sectional area. Conversely, resistance is inversely proportional to the cross-sectional area, meaning a thicker wire would have lower resistance.21