Light

1. Red
2. Orange
3. Yellow
4. Green
5. Blue
6. Indigo
7. Violet

Nota:

• A luminous objects is one that is a source of light.  A non-luminous object is one that reflects light from another source.

Nota:

• How do we see colours?  a coloured object will absorb all the colours of the spectrum apart from its own, and reflects that colour.  So a green ball will reflect the green light and absorb all the rest of the colours.  Black however, absorbs all the colours of the spectrum, so where you see a black object you are actually seeing an absence of light.
• Primary Colours Red, Yellow, Blue

Nota:

• Refraction is when light is bent.  when rays of light enter something more dense than air, they slow down and refract towards the normal line.  this is why a pencil in water looks bent.