Bennett Mechanical Comprehension Practice Test 2026 - Free Practice Questions and Review Guide

Electric power in the context of an electrical circuit is defined as the rate at which electric energy is transferred. This is typically measured in watts (W), where one watt is equivalent to one joule of energy transferred per second. In practical terms, when electric current flows through a circuit, it can do work on resistors, motors, or other devices, and the amount of work done per unit of time is what constitutes power.

This understanding stems from the formula for electric power, which is given by the product of voltage (the electrical potential difference) and current (the flow of electric charge). Therefore, it emphasizes not only the flow of current but also how quickly energy is being used or converted into another form (like light, heat, or mechanical motion).

The other options focus on different electrical concepts: "Rate of current" suggests a measurement of how much charge flows, but it does not quantify energy transfer. "Charge per second" seems to reference current, yet it does not capture the concept of energy. "Differential voltage" pertains to potential difference and voltage measurement but lacks the connection to energy transfer rate. Thus, the correct answer reinforces the critical role of power in electrical circuits as a measure of energy transfer efficiency.