Metals have low resistivities in the range of _________.

The correct answer is 2) 10^-8 Ωm to 10^-6 Ωm.

Key Points

• Metals are known to have very low resistivities, typically in the range of 10^-8 Ωm to 10^-6 Ωm.
• This low resistivity is a result of the high density of free electrons available for conduction in metals.
• Common metals such as copper and aluminum have resistivities close to 1.68 x 10^-8 Ωm and 2.82 x 10^-8 Ωm, respectively.
• The low resistivity of metals makes them ideal for use in electrical wiring and components where minimal energy loss is crucial.

Additional Information

• Conductivity: The reciprocal of resistivity, conductivity (σ) indicates how well a material can conduct electric current. Metals have high conductivity due to their low resistivity.
• Ohm's Law: The relationship between voltage (V), current (I), and resistance (R) is defined by Ohm's Law: V = IR. Low resistance in metals ensures that they can carry large currents with minimal voltage drop.
• Temperature Coefficient: The resistivity of metals increases with temperature. The temperature coefficient of resistivity quantifies this relationship.
• Applications: Due to their low resistivity, metals are widely used in electrical and electronic applications such as cables, connectors, and circuit boards.
• Alloys: Sometimes pure metals are alloyed to improve mechanical properties while maintaining acceptable levels of electrical conductivity.