## Cone of the rainbow

This illustration shows
the two rainbows: the primary and the secondary. The illustration
shows that if the person on the ground moves, or the sun moves,
i.e. the angle of the sunrays relative to the ground changes, the
rainbows move as well; but the angle between sunrays and the
observed rainbows are unchanged! The angles are shown with blue
arcs. (»**Marks**« has been selected in The Rainbow's menu).

The angle can be
measured on a printout, but don't forget to choose
angle-preserving printout.

Exercise 1

Notice the order of
the colors in the rainbows and measure the angles between
sunrays and light from the rainbow for red and violet in both
rainbows with an angle meter.

Exercise 2

Use the above
picture of the Earth at 12 o'clock (noon) at winter solstice
to find the sun's altitude above the horizon.

Draw a corresponding
picture of the Earth at 12 o'clock (noon) at summer solstice.
At what altitude is the rainbow observed at those times?

What is the altitude
of the rainbow when the sun is on the horizon?