Ground gradient is best described as which of the following?

• A. A measure of soil moisture content.
• B. A protective device.
• C. A type of electrical conductor.
• D. Electrical field that radiates outward from where the current enters the ground; its intensity dissipates rapidly as distance increases from the point of entry.

Answer: (D)

Ground gradient is the electrical potential field in the earth created when current enters the ground. It radiates outward from the point of entry and its intensity drops off rapidly with distance. This means the electrical risk is greatest close to where the current enters and decreases as you move away. It’s not about soil moisture, not a protective device, and not a conductor; it’s the way the electric field behaves in the ground near a fault or energized source.