|
Rainbows
are beautiful arcs of colour in the sky.
 |
They occur when it is raining and
sunny at the same time.
To see one you have to stand with
your back to the sun.
|
The sun gives off light. The light we can
see is called 'white light'. But this white light isn't
actually white at all, it is made up many different colour
wavelengths.
The main colours are red, orange, yellow, green,
blue, indigo and violet. These seven colours are called the
colours of the spectrum. The longest wavelength is red and the
shortest is violet.
Many people use the
phrase 'Richard Of York Gave Battle In Vain' to help them
remember the colours of the rainbow.
|
 |
Separating the
colours
To separate these seven
different colours from the white light, you can use a prism
(a triangular-shaped piece of glass).
The prism separates
the white light into the different colour wavelengths by
bending each light ray at a different angle and so separating
the colours. The separation of white light into different
colours is called 'dispersion'. When the prism bends each
light ray, this is called 'refraction'.
So the reason we get rainbows in the sky
is because the raindrops act like lots of tiny little prisms.
As the sun shines white light through the sky, the raindrops
separate it into the seven main colours, forming a rainbow.
Activities
Why not try creating your own phrase to
remember the colours of the rainbow?
Why not draw your own rainbow and
then colour it in? Try to use the right colours in the right
order.
|
