Electrician's Licensing Practice Exam

What is the relationship between voltage, current, and resistance as per Ohm's Law?

1. Voltage = Current + Resistance

2. Voltage = Current x Resistance

3. Current = Voltage / Resistance

4. Resistance = Voltage + Current

The correct answer is: Voltage = Current x Resistance

Ohm's Law is a fundamental principle in electrical engineering that defines the relationship between voltage, current, and resistance. According to Ohm's Law, the voltage across a conductor is directly proportional to the current flowing through it, with the resistance of the conductor acting as the proportionality constant. The correct formulation of Ohm's Law is expressed mathematically as Voltage = Current x Resistance. This means that if you know the value of current (in amperes) and resistance (in ohms), you can easily calculate the voltage (in volts) across the circuit. This foundational relationship allows electricians and engineers to analyze and design electrical circuits effectively. The other options do not accurately reflect this relationship. For instance, stating that Voltage equals Current plus Resistance misconstrues the basic concept, as voltage does not equate to a simple sum of current and resistance. Similarly, expressing current as Voltage divided by Resistance, while it reflects another valid rearrangement of Ohm's Law, does not directly define the original relationship. Lastly, claiming that Resistance equals Voltage plus Current misrepresents how these three variables interact according to electrical principles.