Which factors determine the resistance of a conductor?

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Multiple Choice

Which factors determine the resistance of a conductor?

Resistance in a conductor is set by how easily electrons can flow through the material, which depends on four factors: the material’s inherent resistivity, the length of the path the current must travel, the cross-sectional area of that path, and the temperature. In formula form, R = ρL/A, where ρ is the resistivity of the material, L is the length, and A is the cross-sectional area. This means longer conductors offer more opposition to current, smaller cross-sections restrict more and raise resistance, and higher temperatures typically increase resistivity for metals, raising resistance. Different materials have different intrinsic resistivities, so the same geometry can have different resistance in different materials. Color and weight don’t affect how electrons move through a conductor. Voltage and current are related by Ohm’s law (V = IR); they describe what happens given a resistance, not what determines the resistance itself. Shape alone isn’t sufficient because what matters is the actual length and cross-sectional area, along with the material’s properties and temperature.

Resistance in a conductor is set by how easily electrons can flow through the material, which depends on four factors: the material’s inherent resistivity, the length of the path the current must travel, the cross-sectional area of that path, and the temperature. In formula form, R = ρL/A, where ρ is the resistivity of the material, L is the length, and A is the cross-sectional area. This means longer conductors offer more opposition to current, smaller cross-sections restrict more and raise resistance, and higher temperatures typically increase resistivity for metals, raising resistance. Different materials have different intrinsic resistivities, so the same geometry can have different resistance in different materials.

Color and weight don’t affect how electrons move through a conductor. Voltage and current are related by Ohm’s law (V = IR); they describe what happens given a resistance, not what determines the resistance itself. Shape alone isn’t sufficient because what matters is the actual length and cross-sectional area, along with the material’s properties and temperature.

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