Electrolysis Practice Exam

What happens to direct current in a circuit?

1. It changes directions constantly

2. It flows from negative to positive

3. It flows from positive to negative

4. It creates electromagnetic fields

The correct answer is: It flows from positive to negative

Direct current (DC) is characterized by the unidirectional flow of electric charge. In a circuit using DC, electrons flow consistently in a single direction, which is from the negative terminal to the positive terminal of a power source. This is fundamentally different from alternating current (AC), where the direction of the current changes periodically. Therefore, the statement that direct current flows from positive to negative provides an accurate description of the conventional flow of electric current. It is essential to understand that in terms of electron movement, the actual flow of electrons is from negative to positive; however, the conventional current flow is described as traveling from positive to negative. In the context of the other options, option regarding changing directions does not apply to direct current, as that behavior is characteristic of alternating current. The option mentioning electromagnetic fields is more relevant to both AC and DC currents, but it does not specifically define the nature of current flow in a DC circuit. Thus, understanding the nature of DC as a stable, single-directional flow underlines why the focus on the flow direction from positive to negative is significant.