Cathodic Protection Tester Practice Exam

Resistance is defined as what?

1. The flow of current through a circuit

2. The opposition that a charge encounters when it moves through a material

3. The total energy in a system

4. The amount of voltage in a circuit

The correct answer is: The opposition that a charge encounters when it moves through a material

Resistance is defined as the opposition that a charge encounters when it moves through a material. This concept is fundamental in electrical engineering and physics, as it determines how easily electric current can flow through different materials. In this context, resistance can be influenced by several factors, including the material's properties, temperature, and physical dimensions. Understanding resistance is critical for anyone working with electrical systems, including cathodic protection systems, because it affects the efficiency and effectiveness of current flow. High resistance materials impede current flow, which can lead to inadequate corrosion protection in cathodic systems, while low resistance materials allow for better current distribution. The other options presented do not accurately define resistance. The flow of current refers to the movement of charge, not the opposition to it; total energy relates to the work done by electric currents rather than the resistance encountered; and voltage is a measure of the electric potential difference, not the opposition to flow. Thus, defining resistance as the opposition to charge movement provides the clearest understanding of this essential electrical property.