Ohm's Law & Series/Parallel Circuits

Ohm's Law (V=IR) relates voltage, current, and resistance; series and parallel resistor combinations follow different rules for total resistance.

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Overview

In series, resistances add directly: R_total = R1+R2+.... In parallel, reciprocals add: 1/R_total = 1/R1 + 1/R2+.... This means total parallel resistance is always LESS than the smallest individual resistor — a commonly misunderstood result.

Practice Quiz

Question 1 of 1Score so far: 0/0

Two identical resistors of resistance R are connected in parallel. What is the total (equivalent) resistance?