What is step potential?

What is step potential?

• A. Occurs when voltage increases uniformly away from the source.
• B. Occurs when a solid conductor becomes magnetized.
• C. Occurs when an energized source creates a gradient across the surface as a result of current flowing outward in decreasing voltage.
• D. Is the same as touch potential.

Answer: (C)

Step potential is the voltage difference that appears on the ground surface around an energized source because the current flows through the earth and creates a gradient. Closer to the source, the ground is at a higher potential; as you move away, the potential drops. This creates a varying voltage across the surface, so if two points are a step apart (like your two feet), there can be a current path through the body from one foot to the other. The wording in the option captures this idea: the energized source produces a surface gradient as current flows outward and voltage decreases with distance from the source. This is distinct from a uniform rise in voltage or from magnetization of a conductor, and it’s not the same as touch potential, which refers to the voltage at a single contact point rather than across the surface between points.

Step potential is the voltage difference that appears on the ground surface around an energized source because the current flows through the earth and creates a gradient. Closer to the source, the ground is at a higher potential; as you move away, the potential drops. This creates a varying voltage across the surface, so if two points are a step apart (like your two feet), there can be a current path through the body from one foot to the other.

The wording in the option captures this idea: the energized source produces a surface gradient as current flows outward and voltage decreases with distance from the source. This is distinct from a uniform rise in voltage or from magnetization of a conductor, and it’s not the same as touch potential, which refers to the voltage at a single contact point rather than across the surface between points.