ASTB Mechanical Comprehension Practice Exam

The formula for calculating electrical power is given by the relationship between voltage and current. Specifically, power can be expressed in terms of voltage (measured in volts) and current (measured in amperes). The correct formula states that power equals voltage multiplied by current, which means that the energy consumed or generated per unit of time is the product of these two quantities.

In practical terms, when you have a circuit applying a certain voltage across a load and that load draws a certain amount of current, multiplying these two values gives you the total power being used by that load. This relationship is fundamental in electrical engineering and helps in designing circuits, understanding energy consumption, and analyzing electrical systems.

The other options do not accurately represent the relationship between voltage, current, and power. While it's true that coulombs are related to electric charge, they do not directly factor into the power calculation in the simple framework provided by the correct formula. Additionally, dividing amperes by volts does not yield a meaningful measurement of power—this is more reflective of resistance when applying Ohm's law. Therefore, the correct answer reinforces the foundational concept that electrical power is a function of both voltage and current.