AMPP Cathodic Protection Technician (CP2) 2025 – 400 Free Practice Questions to Pass the Exam

The relationship between voltage difference and current flow is rooted in the principles of electrochemistry. When two different metals are in contact with a conductive medium, a voltage difference between them can drive an electrochemical reaction. The greater the voltage difference, the greater the potential energy available to drive the electrons from one metal to the other, which in turn results in increased current flow.

Current flow is directly related to the driving force provided by this voltage difference, as described by Ohm's Law (V = IR), where V is voltage, I is current, and R is resistance. In a cathodic protection context, when the voltage difference is higher, it indicates a stronger electrochemical potential that promotes electron movement. This means that more electrons can potentially be transferred, leading to higher current flow.

Additionally, a higher current flow contributes to an increased rate of corrosion for the metal that is losing electrons, as the metal atoms are oxidized, leading to material loss over time. Therefore, a greater magnitude of voltage difference will indeed lead to higher rates of current flow and, consequently, an accelerated rate of corrosion. This principle is essential in understanding how to effectively use cathodic protection systems to mitigate corrosion in various metal structures.