How Electronics Work
Learn how electricity moves through circuits, powers components, and responds to controls. Build real intuition for voltage, resistance, and transistors through practical circuit design. Go from a bare battery to building responsive, sensor-driven hardware.
Like Duolingo, but for How Electronics Work. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
A short one: 12 levels across 2 sections, about 24 minutes end to end, roughly 5 days at five minutes a day. It moves through Making Circuits Work and Sensing and Switching. It starts from scratch.
Free forever · No credit card · iPhone & Android
Key ideas in How Electronics Work
- Electricity will not flow unless there is an unbroken path leading from power back to ground
- A single connection from power delivers voltage potential, but no current moves without a completed return loop
- Voltage is the pushing force that drives charge through a circuit
- Current measures how much charge actually flows past a point per second
- Resistance restricts how freely that charge can move under a given voltage
- An LED is a one-way gate (diode) that only allows current to pass from its positive leg (anode) to its negative leg (cathode)
- The longer lead of a standard through-hole LED indicates the anode and must point toward the positive supply
- Connecting an LED backwards blocks the flow of current and keeps it unlit
- LEDs offer very little internal resistance once turned on
- Without an inline resistor, an LED pulls runaway current beyond its thermal limit
- Excessive current instantly overheats and destroys the tiny semiconductor junction inside the LED
- A short circuit occurs when power connects directly back to ground without traveling through a load
- Zero-resistance paths cause current to surge to dangerous levels
- The sudden massive surge of current generates rapid heat in the wiring and power supply
- Resistance restricts the rate of electrical charge (current) flowing through a circuit
- Higher resistance lowers the current for a fixed voltage source, making components like LEDs dimmer
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives How Electronics Work the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
Imagine you attach a single wire from a battery to a motor, but don't connect a return wire back to the battery. What happens?
Get it right to open this lesson and 11 more in the app.
Where How Electronics Work takes you
- 1
Making Circuits Work
- Completing the Loop
- Controlling Current Flow
- 2
Sensing and Switching
- Switching with Transistors
- Prototyping Interactive Circuits
2 sections · 4 units · 12 levels. Built to play, not to enroll.
Tomo is in ChatGPT
Tomo is also a ChatGPT plugin: the same playable courses, built and played inside your chat.
Add Tomo to ChatGPT- What to ask
- “Make me a Tomo course on black holes.” “Turn this chat into a Tomo course.”
- What you get
- Quick questions with instant feedback, hearts and stars, ready to play in about a minute.
- Where it goes
- No sign-up to start. Connect your Tomo account and your streak carries on in the app.
You pick the voice
How Electronics Work is taught in the Storyteller style: every lesson is a story. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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How Electric Circuits Work
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How Circuits Work
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The Flow of Power: Basic Circuits
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The Flow of Power
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Start How Electronics Work today.
Download Tomo, search How Electronics Work, and play your first lesson in under a minute.