Resistors both in Series and In Parallel
In this article, we'll do a resistor circuit in which resistors are both in series and in parallel in the same circuit.
First, we can start by finding the resistance of the resistors in series. In the first branch, containing the 20Ω and 40Ω resistors, the series resistance is 60Ω. And in the second branch, containing the 30Ω and 60Ω resistors, the series resistance is 90Ω. Now in total, the circuit has 3 resistances in parallel, 10Ω, 60Ω, and 90Ω. Now, we plug these 3 values into the parallel resistance calculator and get a total resistance of 7.83Ω.
If you want to test the above series and parallel connections out practically, get 1KΩ resistor or whatever resistors you have, but let them be of the same value. In this example, I'll stick with 2 1KΩ resistors. Take the resistors and place them in series. Now take a multimeter and place the multimeter in the ohmmeter setting and place the probes over the 2 resistors. You should read just about 2KΩ, which is double the value of both resistors. This proves that resistors add when connected in series. Now place the resistors in parallel. Take the multimeter probes and place one end on one side of a resistor (either one) and place the other probe on the other side of that resistor. You should now read about 0.5KΩ, or half the value, because resistance in parallel decreases. This is a practical, real-life test you can do to show how resistors add.