Interact with the concepts before or after the lessons.

Demo 1

Touch and conductivity

Every slab is the same room temperature (20 °C), yet they don't feel the same. Tap a material to press your fingertip against it and watch heat drain out of your skin — fast for metal, barely at all for wood — on a live temperature graph.

Demo 2

Visible light — colour and photon energy

Sweep across the visible spectrum. See the colour your eye perceives, watch the photon stream, and read how much energy each photon carries (E = hc/λ).

Demo 3

Kitchen echo — clap and listen

Drag from soft furnishings to hard tile, then clap. Hear the kitchen ring longer, and watch the sound energy take more time to fade to silence.

Demo 3b — a real instrument

See the sound of your kitchen — and tune to it

This one listens. Hum, whistle, run the tap, or stand near the fridge — the live spectrum shows every frequency your kitchen is making. It is also a real chromatic tuner: sing or play a note and it names it, shows how many cents sharp or flat you are, and marks the musical scale (every C, plus A4 = 440 Hz) right on the frequency axis — so you can tune a guitar with it, or see that each octave is a doubling. Everything stays on your device; nothing is recorded or sent.

Tip: a fridge compressor hums near 50–120 Hz; a kettle's hiss lives in the kilohertz. Guitar strings, low to high: E2 · A2 · D3 · G3 · B3 · E4.

Demo 4

Phase-change ladder — feel the hidden energy

Press Heat to pour energy into a pot of ice. The thermometer climbs… then stalls at 0 °C and again at 100 °C, even as you keep heating. Those flat steps are latent heat.

Demo 5

Particle view of heating water

Watch individual particles move through solid, liquid, and vapor as you raise the temperature.

Demo 6

Sound lab

Play a pure tone, change its frequency and loudness, and watch the waveform tighten as the pitch rises.

Demo 7

Pressure and boiling point — the pressure cooker

Change the pressure pressing on the water, from a thin-aired mountaintop to a sealed pressure cooker, and watch the temperature at which it boils move with it.

Demo 8

Specific-heat race — same heat, different climb

Pour identical heat into equal masses of an iron pan, oil, and water. Watch how differently their temperatures rise — the reason a dry pan scorches while a pot of water heats slowly.

Demo 9

Convection loop — why the pot stirs itself

Turn up the flame under a pot and watch the water set up a circulating loop: hot water rises up the middle, cools at the top, and sinks down the sides.