1.1. The speed (and also normally the direction) changes at the boundary between the two media.
1.2. Refraction occurs when light changes the 'medium' (substance or thing) it is travelling through.
2. Reflection
2.1. THE NORMAL IS ALWAYS AT A 90. ANGLE TO THE MIRROR
2.2. ANGLE OF INCIDENCE = ANGLE OF REFLECTION
2.3. CLEAR REFLECTION IS ONE OF A SMOOTH, CLEAN SURFACE. A DIFFUSE REFLECTION IS ONE OF A DULL, JAGGED SURFACE
3. Dispersion
3.1. DISPERSION IS WHEN WHITE LIGHT IS DIVIDED INTO THE COLOURS OF THE SPECTRUM
3.2. The process in which a rainbow is formed: When a light beam happens to hit a rain drop at a certain angle, the different colours that white is made of are separated in the form of a rainbow because each one is being refracted a different amount.
4. colour
4.1. White light is made up of all the colours of the spectrum.
4.2. The primary colours of light are red, blue and green
4.3. A pair of purple trousers would reflect purple light (and red and blue, as purple is made up of red and blue)
4.4. A white hat would reflect all three colours:
4.5. Ed’s T-shirt is yellow because it reflects yellow light, but absorbs all other colours of the spectrum shining on it.
4.6. Filters - only let the colour pass that they are, all other colours are absorbed.
4.7. For example if you had a red filter and shined white light on it ONLY red light would come out
