2nd Year Lineman Apprentice Practice Exam 2026 - Free Lineman Apprentice Practice Questions and Study Guide

In a series circuit, all components, including resistors, are connected end-to-end, creating a single path for current to flow. When resistors are added in series, the total resistance of the circuit increases because the resistances simply add together. According to Ohm's Law, which states that current (I) equals voltage (V) divided by resistance (R), as the total resistance in the circuit increases and if the voltage source remains constant, the overall current flowing through the circuit must decrease.

This means that the more resistors added in series, the greater the overall resistance, and thus the lower the overall current in the circuit for a given voltage. So, if you have a fixed voltage supply and add more resistors in series, the current decreases because the circuit offers more opposition to the flow of electricity.