Contents
Year 518 · Light
KO

Year 5 · second unit

Light

Light goes straight. But meeting a mirror it bounces, and meeting water it bends. Those three things are the whole of this unit.

A child making shadow shapes on a wall with a torch

I held my hand in front of a torch

A board to adjust

What happens to the shadow if you drag the hand back and forth?

A huge hand shadow on a wall

Bounce light off a mirror to hit the box

A board to adjust

Drag sideways on the board to turn the mirror. Where will the light go?

A child bouncing sunlight off a small mirror

I try to pick up a coin under water and keep missing

A board to adjust

Pour in water and look from the side: where does the coin seem to be?

A hand reaching for a coin at the bottom of a cup of water

From here angles come in

What comes next in middle school · light and waves

The angle it bounces, the angle it bends

It is the light that bounced and bent above. Hold a protractor to it and the rules come out exactly. A mirror: the same angle. Water: a fixed ratio.

The path of light with a protractor on it, on dark paper

The light that bounced above

A board to adjust

This time there are angles. Switch between mirror and water and turn the angle coming in.

30°angle of incidence
30°angle of reflection

Back up to the basics