Point at or tap any part to see its name. Tap a wire to break it, and tap it again to join it. Tap the switch to flip it.
Amber dots show current. Their speed and spacing show amps, not how fast electrons move. In these wires the electrons drift only a fraction of a millimeter per second.
The dots move from plus to minus, the way electricians draw current. Electrons move the other way.
On 120 volts AC, the voltage reverses 120 times a second, so the current really goes back and forth. The dots show one direction to keep the loop simple. The "AC and DC" visual shows the back and forth.
On the 120 volt setup, a red glow means live to ground and blue means 0 volts. Gray dashes mean the wire is not connected to anything. The white neutral is connected to the earth at the service, so it stays near 0 volts.
The 120 volts comes from the utility transformer, through the feeders, into the panel. The white neutral carries the current back to the transformer the same way.
In the wall, the black, white, and bare wires run together in one cable. They are drawn apart here to show the loop.
"Lamp to ground" is the voltage from the lamp to ground. It uses whichever lamp screw reads higher. It turns red when the lamp is dark but still live.
Current does not flow into the earth by itself. When the white comes apart, the current stops. The bare ground wire carries no current here. It is there for faults.
The battery is four 1.5 volt D cells in a row, which makes 6 volts. The lamp is rated 6 volts and 3 watts, so it has 12 Ω of resistance when lit. The model leaves out the battery's own resistance.
The 120 volt lamp is 60 watts, so it has 240 Ω of resistance when lit. The house wiring is 50 ft of 14 AWG copper each way, at 3.07 Ω per 1,000 ft. The lamp cord is 6 ft of 18 AWG, at 7.95 Ω per 1,000 ft. Both values come from Chapter 9, Table 8. A 15 A breaker protects the 14 AWG copper, 240.4(D)(4).
Test before you touch, every time (trade practice). A dark lamp is not proof that nothing is live.
In a home, most rooms also need AFCI protection, 210.12(B). It is not drawn.
Wires shown pulled apart are a failed splice or a broken wire, not a cut made on a live circuit. The drawing is not to scale.