Light
Map
Arrows point from what you learn first to what it opens. Point at a concept to light up its chain and where it comes back deeper. Right-click a concept (or press and hold it) for its lessons and stories.
- Proven to depth123
- Open
- Locked
- Comes back deeper
Learning path
In the order the concepts build on each other.
- Light sourcesReadySome things make their own light: the Sun, a fire, a lamp, even a firefly. These are light sources. Most things don't make light. We see them only because light from a source bounces off them. The Moon has no light of its own either: it shines with sunlight.
- ReflectionLockedLight travels in straight lines until it hits something. Then some of it bounces off: that is reflection. Smooth, shiny things like mirrors and still water reflect light neatly, so you can see a picture in them. Rough things scatter it every way.Opens after: Light sources
- How we seeLockedWe see a thing when light from it reaches our eyes. A lamp sends its own light into our eyes. A book is seen because light from a lamp or the Sun bounces off it into our eyes. In a completely dark room you see nothing, because no light comes to your eyes.Opens after: Reflection
- MirrorsLockedA flat mirror shows things the same size, but with left and right swapped. A mirror that curves inwards, like the inside of a spoon, can make things look bigger close up: a make-up or shaving mirror. A mirror that bulges outwards shows a wider view with everything smaller, like a car's side mirror or the round mirror at a sharp bend in a road.Opens after: Reflection