Nate Electrical Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

The primary distinction between alternating current (AC) and direct current (DC) lies in the direction of flow. AC reverses direction periodically, meaning it changes its flow direction at regular intervals, which is common in power supplies for homes and businesses. This frequent change in direction allows AC to be transformed to different voltages easily, making it ideal for long-distance power transmission.

In contrast, DC flows consistently in one direction, providing a stable voltage level. This characteristic is particularly useful in battery-operated devices and electronic circuits where a constant voltage is necessary.

The other options reflect common misconceptions. While it's true that AC is typically used in outlets and DC in batteries, this doesn't define their fundamental difference. Higher voltage does not inherently apply to AC over DC; they can both operate at various voltage levels depending on the specific application or design requirements.