What a learner can do afterwards
- Draw a circuit diagram for a cell, switch, and bulb using standard symbols
- Identify from a diagram whether a switch is open or closed and predict whether the bulb lights
- Match a photograph of a physical circuit to the correct circuit diagram from a set of options
The lesson
A circuit diagram is like a map for electricity. Instead of drawing a real battery or bulb, we use simple symbols. Straight lines stand for wires, and each symbol stands for one part.
Two lines, one long and one short, mean a cell. A circle with an X inside means a bulb. A break in the line with a small lever means a switch. A circle with a flat line means a buzzer.
Mia draws a circuit with one cell, one switch, and one bulb. She draws the cell, then a wire out to the switch, then a wire on to the bulb, then a wire back to the cell, so the loop closes all the way around.
To read a diagram, trace the loop with your finger starting at the cell. If you get all the way around with no gaps, the circuit is complete and the bulb lights. If the switch shows a gap, the loop is broken and the bulb stays dark.
A circuit diagram uses symbols for cells, bulbs, switches, and buzzers joined by wire lines, and the loop must be unbroken for the bulb to light.
Watch it
Where it sits
Learn first
Nothing; this is a starting point.
This opens up
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.