Recreational Vehicle (RV) Technician Practice Test

A short circuit is a complete circuit that has?

1. No voltage

2. No resistance

3. High resistance

4. Low current

The correct answer is: No resistance

A short circuit is characterized by having no resistance, which allows a large amount of current to flow through the circuit with minimal opposition. In a typical electrical circuit, resistance plays a vital role in controlling the amount of current that flows. However, in a short circuit situation, when there is an unintended path that bypasses the normal load, the resistance drops significantly—close to zero. This results in a dramatic increase in current, which can be hazardous, as it may lead to overheating, tripped breakers, or even fires if the circuit isn't properly protected. The other options suggest conditions that do not accurately define a short circuit. For instance, if there were no voltage, the circuit wouldn't function, and if there were high resistance, the current would also be significantly limited. Low current would indicate that the circuit is not shorted since a short circuit typically allows excessive current flow. Understanding the relationship between voltage, current, and resistance is crucial for recognizing the dangers associated with short circuits.