How Electricity Works
Demystify the invisible force that powers modern life. Learn how circuits operate, what voltage and wattage actually measure, and how electricity safely runs your home.
Like Duolingo, but for How Electricity Works. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
24 levels across 3 sections, about 48 minutes end to end, roughly 10 days at five minutes a day. It moves through Making Circuits Work; Power, Safety, and the Grid; and The Physics Under the Hood. It starts from scratch.
Free forever · No credit card · iPhone & Android
Key ideas in How Electricity Works
- Electricity must complete a continuous path from one terminal of the power source all the way back to the opposite terminal
- A single connection cannot sustain current; charge cannot flow without a closed return path
- The light bulb must sit inside the full loop, not at a dead end
- Air is an insulator that prevents low-voltage current from jumping across
- A switch works mechanically by breaking the continuous physical path of the circuit
- Opening the switch immediately drops current flow in the entire loop to zero
- Current takes the path of lowest resistance, skipping the device entirely
- Without a working load (like a bulb or motor) to limit flow, an enormous surge of current rushes through the wire
- High current in a near-zero resistance wire causes rapid, dangerous overheating and battery drain
- Metals let electric charges move through them easily and act as conductors
- Materials like rubber, glass, and plastic hold charges tightly and act as insulators
- Insulators are used to coat wires to prevent accidental contact and shorts
- Batteries convert stored chemical energy into electrical energy through reactions
- Batteries act like pumps moving existing charges, rather than holding a reservoir of static electricity
- Current entering one terminal must match the current leaving the opposite terminal
- Voltage is the push or pressure that moves electrical charge
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 Electricity Works 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.
You connect a wire from a battery's positive end to a bulb, but leave the other end free. What happens?
Get it right to open this lesson and 23 more in the app.
Where How Electricity Works takes you
- 1
Making Circuits Work
- Building a Working Circuit
- Voltage, Current, and Resistance
- Series and Parallel Connections
- 2
Power, Safety, and the Grid
- Watts, Energy, and Electrical Ratings
- Household Electrical Safety
- Alternating Current and the Grid
- 3
The Physics Under the Hood
- Electromagnetism and Motors
- Charge, Fields, and Electrons
3 sections · 8 units · 24 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 Electricity Works is taught in the The Professor style: clear, structured, thorough. 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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Start How Electricity Works today.
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