← Circuit Lab course

The lab · lesson 6 capstone

Where the volts go

Each moving dot is one scoop of charge. Bright = carrying energy. Dim = energy spent. Drag the sliders and watch what changes.

12 V V reads 12.0 V 1.0 Ω drops 7.0 V 1.0 Ω 5.0 A 2.5 Ω 2.0 A both drop 5.0 V 7.0 A in

Change something

12.0 V
1.0 Ω
1.0 Ω
2.5 Ω

Set both parallel resistors the same and the current splits 50/50 — the dots move at identical speeds.

What the meters would say

Voltmeter reading12.0 V
Total current from battery7.0 A
p.d. across series resistor7.0 V
p.d. across parallel pair5.0 V
Current · top branch5.0 A
Current · bottom branch2.0 A
Combined parallel resistance0.71 Ω

The top branch is the easier road, so more charge takes it.

Break the circuit

Everything connected — current flows as normal.

Energy budget · every scoop spends everything before it gets home

series 7.0 V
parallel 5.0 V

7.0 V + 5.0 V = 12.0 V supplied by the battery.