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violet as they seem to appear to be the same colour.

It is only when the rainbow is very bright that it is
possible to distinguish all seven of the colours.

When you have a bright rainbow you will also have
secondary refraction which gives rise to a second

rainbow. An interesting feature of the secondary

rainbow is the reversal of the colour positions. When
you have an exceptionally bright rainbow you may

even see a third rainbow as well.

An interesting feature regarding the rainbow is the
position of the sun in the sky. The lower the sun on

the horizon, the greater the arc of the rainbow.
Sometimes it is possible to see the complete semi-

circular arc of a rainbow, but usually it is only possible

to see a small section of the rainbow.

This is a well-known story that if you can reach the end
of the rainbow you will find a pot of gold, the only

problem is as you move around the rainbow also
moves, so in principle you can never ever get to the

end of the rainbow.

This completes Lesson 32

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