How to Calculate Resistors in Series & Parallel
What is Resistors in Series & Parallel?
Resistors can be connected in series (end-to-end, increasing total resistance) or parallel (side-by-side, decreasing total resistance). Understanding these configurations is fundamental to circuit analysis and electronics design.
Step-by-Step Guide
- 1Series: R_total = R1 + R2 + R3 + ... (resistances add)
- 2Parallel: 1/R_total = 1/R1 + 1/R2 + 1/R3 ... (reciprocals add)
- 3Two resistors in parallel: R_total = (R1 × R2) / (R1 + R2)
- 4Voltage divides in series; current divides in parallel
Worked Examples
Input
100Ω and 100Ω in parallel
Result
50Ω total
(100×100)/(100+100) = 50
Input
100Ω and 100Ω in series
Result
200Ω total
Simple addition
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