ABYC Marine Electrical Practice Exam

If voltage increases, what happens to amperage?

1. It decreases

2. It remains constant

3. It increases

4. It fluctuates

The correct answer is: It increases

The relationship between voltage and amperage is governed by Ohm's Law, which states that voltage (V) equals current (I) multiplied by resistance (R), or V = I × R. From this relationship, if voltage is increased while resistance remains constant, the current (or amperage) must also increase. This is because resistance in a circuit does not change simply because voltage increases; thus, any rise in voltage will proportionally raise the current to maintain the balance dictated by Ohm's Law. In practical terms, this principle applies to many electrical systems, including those commonly found in marine applications. For instance, if a boat's battery voltage increases, more current can flow through the same load, provided that the resistance within the circuit does not change. This understanding is crucial for any electrical troubleshooting or design, as it helps predict how changes in voltage can impact the overall current in a system. Understanding this concept is vital for marine electricians and anyone involved in the electrical systems on boats, as it affects both performance and safety in managing electrical loads.