Which of the following materials has the lowest resistivity at 20°C?

Silver is known for having the lowest resistivity among common electrical conductors at 20°C, making it the material of choice in applications requiring high conductivity. This property is due to its atomic structure, which allows electrons to flow more freely compared to other materials. Silver's resistivity is approximately 1.59 x 10^-8 ohm-meters, making it an excellent conductor for various electrical applications, including high-frequency systems and specialized wiring.

While other materials like copper and aluminum are also good conductors, their resistivities are higher than that of silver. Copper, for instance, has a resistivity of around 1.68 x 10^-8 ohm-meters and is widely used in electrical wiring due to its balance of conductivity, cost, and mechanical properties. Aluminum, although lighter and cheaper, has a resistivity of approximately 2.82 x 10^-8 ohm-meters, making it less conductive than silver and copper.

Brass, an alloy primarily composed of copper and zinc, also has a higher resistivity than pure copper and significantly higher than silver, further confirming its inefficiency as a conductor in comparison to the other options presented.

Thus, understanding the properties and resistivities of these materials is essential