Resistivity is defined as what?

Resistivity is defined as the opposition that electric charges encounter when moving through a material. This property is intrinsic to the material and is quantified by the resistivity value, which varies depending on factors such as temperature and the material's composition. A higher resistivity indicates that the material resists the flow of electrical current more than a material with lower resistivity.

This concept is fundamental in the context of cathodic protection because it directly impacts the effectiveness of the protection measures in different soil or environmental conditions. Understanding resistivity helps in assessing the suitability of a given location for cathodic protection systems, particularly in terms of how much current will flow through the ground or other materials used.

In contrast, the other choices do not accurately define resistivity. The measure of flow refers to current, the total electrical charge describes a different concept in electrostatics, and the resistance of a complete circuit relates to Ohm's Law but does not pertain specifically to resistivity as it defines materials' properties. Therefore, the definition emphasizing opposition to current flow is essential for grasping the concept of resistivity in both theoretical and practical applications.