Series & Parallel Circuits
Wire three resistors in series, in parallel, or as one in series with the other two in parallel — watch the current split between branches and the total resistance change, with a parallel path always lowering it and a series one always raising it.
What you can adjust
- Wiring
- 0 – 2
- Supply voltage (V)
- 1 – 24 V
- R1
- 1 – 100 ohm
- R2
- 1 – 100 ohm
- R3
- 1 – 100 ohm
How the three resistors are connected. Series gives current only one path, so the same current flows through every resistor. Parallel gives each resistor its own path across the same voltage — adding a resistor in parallel LOWERS the total resistance, because you've opened another route for current to take.
The DC EMF driving the circuit — 12V is a common real battery voltage. Every resistor's voltage, current, and power scale with this.
In series, raising R1 raises the total resistance and lowers the current everywhere in the loop. In parallel (or as the parallel pair's neighbor in the mixed wiring), raising R1 mostly just means R1's own branch draws less current — the other branches barely notice.
Try setting R2 well below R3 in a parallel (or mixed) wiring — the lower-resistance branch always carries more current, since the same voltage is pushing charge through less opposition.
Set R1, R2 and R3 all equal in the Parallel wiring to see the classic result: three equal resistors in parallel give exactly one third of a single resistor's resistance.