If a current flows in the same direction, what is it called?

If a current flows in the same direction, what is it called?

• A. Alternating current
• B. Direct current
• C. Pulsed current
• D. No current

Answer: (B)

The key idea is how the direction of current changes over time. When the current keeps moving in the same direction, that is called direct current. The fixed polarity of the voltage source (like a battery) pushes charges in one constant direction, so the flow doesn’t reverse. In contrast, alternating current continually reverses its direction, which is typical for power from wall outlets. Pulsed current involves bursts of current, which may still go in one direction during each burst, but the defining trait is the on/off timing rather than a reversal. No current simply means there is no flow at all. So, flow in the same direction is direct current.

The key idea is how the direction of current changes over time. When the current keeps moving in the same direction, that is called direct current. The fixed polarity of the voltage source (like a battery) pushes charges in one constant direction, so the flow doesn’t reverse. In contrast, alternating current continually reverses its direction, which is typical for power from wall outlets. Pulsed current involves bursts of current, which may still go in one direction during each burst, but the defining trait is the on/off timing rather than a reversal. No current simply means there is no flow at all. So, flow in the same direction is direct current.