Series Parallel Resistor Calculator
Calculate equivalent resistance for resistors in series and parallel configurations.
Frequently Asked Questions
How do series resistors add?
In series (end-to-end), total resistance = R1 + R2 + R3... Example: 10Ω + 20Ω + 30Ω = 60Ω. Series increases total resistance. Current is same through all; voltage divides.
How do parallel resistors add?
In parallel (same nodes), 1/Rtotal = 1/R1 + 1/R2 + 1/R3... Example: 10Ω || 20Ω || 30Ω = 5.45Ω. Parallel decreases resistance. Voltage is same across all; current divides.
What is series-parallel combination?
Mixed circuit with some resistors in series, others in parallel. Solve by breaking into sub-networks, find each equivalent, then combine. Work from innermost (most complex) outward.
Why are parallel resistors lower than series?
Parallel provides multiple current paths, reducing total opposition. Series is single path, adding opposition.
What is current division in parallel?
Current splits inverse to resistance: I1/I2 = R2/R1. Lower resistance gets more current.
What is voltage division in series?
Voltage divides proportional to resistance: V1 = Vin × R1/(R1+R2). Higher resistance gets more voltage.
How do I analyze mixed series-parallel?
Identify series segments (add), parallel segments (reciprocal add), then combine. Always work from components outward to total resistance.
What is equivalent resistance?
Single resistor value that would draw same current as the network. Used to simplify circuit analysis.