Series resistance is simply connecting the "out" side of one resistor to the "in" side of another in a circuit. Each additional resistor placed in a circuit adds to the total resistance of that circuit.


The formula for calculating a total of n number of resistors wired in series is:
Req = R1 + R2 + .... Rn
That is, all the series resistor values are simply added. For example, consider finding the equivalent resistance in the image below

In this example,
R1 = 100 Ω and R2 = 300Ω are wired in series. Req = 100 Ω + 300 Ω = 400 Ω
What it is.
{"src": "wikihow-all_validation", "title": "How to Calculate Series and Parallel Resistance2"}