CR104B Vehicle Electrical and Mechanical Systems Practice Test 2026 - Free Practice Questions and Study Guide

Amperage refers to the flow of electric current, the rate at which charge moves through a conductor. It’s measured in amperes (A) and represented by the symbol I. In practical terms, more amperage means more electrons passing a given point each second.

This is different from voltage, which is the potential difference that pushes charges, and from resistance, which is how much a material or component resists that flow. Power, meanwhile, is the rate at which energy is transferred and is calculated as voltage times current. A quick connection between these ideas is Ohm’s law: current equals voltage divided by resistance, showing how voltage and resistance determine the amperage, i.e., the current.