Question

Which of the following graph represents the variation of resistivity $(\rho)$ with temperature (T) for copper ?

• A.
• B.
• C.
• D.

Answer 1

The Correct Option is C

To determine which graph correctly represents the variation of resistivity \((\rho)\) with temperature (T) for copper, we need to understand how resistivity changes in metallic conductors like copper.

Concept: For metals, as the temperature increases, the thermal agitation of atoms increases, leading to a higher resistance to the flow of electrons. As a result, the resistivity of metals such as copper increases linearly with temperature.

The relation of resistivity \((\rho)\) with temperature (T) for a metallic conductor is generally expressed as:

\(\rho(T) = \rho_0 (1 + \alpha T)\)

Here, \(\rho_0\) is the resistivity at a reference temperature (usually 0°C), and \(\alpha\) is the temperature coefficient of resistivity.

This equation showcases a linear relationship, implying that \(\rho\) increases with T.

Given this understanding, we need to look for an option where the graph shows a linear increase in resistivity with temperature.

The image linked above represents a linear graph, which matches the expected increase in resistivity with temperature for copper.

Conclusion: Therefore, the correct graph that represents the variation of resistivity with temperature for copper is the one that showcases a linear increase. This matches the characteristic behavior of metallic conductors, specifically copper, as they heat.