Ontario Operator-in-Training (OIT) Practice Exam

According to electrical principles, what is the formula for voltage?

1. Current + Resistance

2. Current × Resistance

3. Current - Resistance

4. Resistance × Power

The correct answer is: Current × Resistance

The formula for voltage is represented by the relationship between current and resistance as described by Ohm's Law, which states that Voltage equals Current multiplied by Resistance. In mathematical terms, this is expressed as V = I × R, where V is the voltage, I is the current, and R is the resistance. This formula illustrates how voltage is directly proportional to both current and resistance: if you increase either the current flowing in a circuit or the resistance opposing that flow, the voltage across the component will also increase. This principle is foundational in electrical engineering and applied in various practical applications, from circuit design to troubleshooting electrical systems. The other alternatives do not accurately represent the relationship as defined by Ohm's Law. For example, adding or subtracting current and resistance does not yield a meaningful electrical concept related to voltage. Additionally, resistance multiplied by power would not provide the correct expression for voltage as it combines unrelated variables in this context. Understanding this relationship is crucial for anyone studying or working with electrical systems.