Electronics in a Product: Switch, Sensor, Output
Most electrical products are the same three parts: something that decides, something that senses, and something that happens. A switch is a person deciding, a sensor is the product deciding for itself.
What a learner can do afterwards
- Sort the parts of a simple product into input, control and output
- Explain the difference between a switch and a sensor in what triggers them
- Name two sensors and what each measures, such as light or temperature
- Sketch a circuit for a stated behaviour, such as a light that comes on when it gets dark
1 · Read
Most gadgets share three parts: something senses, something decides, and something happens. Spot the three and you can read any product. In a simple radio the antenna catches waves from the air, the tuner picks the station, and the earpiece makes the sound you hear.
A switch means a person decides, like pressing a torch button. A sensor means the product decides for itself, like a garden lamp that notices dark.
A night light that glows at dusk holds a light sensor, a tiny decider, and a lamp. Dark in, choice made, light out.
To sketch a circuit, draw the three in a loop: sense at the start, decide in the middle, and the output at the end.
Sort each part into sense, decide or do, and the product stops feeling like magic.
2 · Watch
Take it off screen
Where it sits
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.