Basic Electricity Practice Exam 2026 - Free Electricity Practice Questions and Study Guide

In a parallel circuit, each resistor provides a separate path for current, so the overall resistance drops. The combined resistance follows 1/R_total = 1/R1 + 1/R2 + ...; this means R_total is always smaller than the smallest individual resistor. For example, 4 Ω and 6 Ω in parallel give R_total = (4×6)/(4+6) = 2.4 Ω, which is less than both 4 Ω and 6 Ω. Adding more parallel paths continues to lower the total resistance.

This is why the total is not the sum of the resistances (that would be a series case) and not the largest resistor. It’s also not larger than the largest resistor because every additional parallel path provides another route for current, reducing the overall resistance.