You can remember the colours of the rainbow (visible spectrum) and get them in the right order by remembering the mneumonic:
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Different colours have different wavelengths. Red light has the lowest amont of energy
and the longext wavelength. Infra-red light has less energy and a longer wavelength than
ordinary red light. You cannot see IR light so it is not part of the visible spectrum.
However you can feel IR light on your skin because it warms you up.
Violet light has the highest amount of energy and the shortest wavelength. Ultra-violet
light has even more energy and a shorter wavelength. UV light cannot be seen but it will
give you sunburn and could give you skin cancer. UV light is not part of the visible
Light is a part of the electromagnetic spectrum. Wavelengths longer than IR light
include microwaves and radiowaves. Wavelengths shorter than UV light include:
- gamma rays and
We call these waves “electromagnetic” waves because they are partly
electrical and partly magnetic. Obvious isn’t it?
Here is a suggestion for your revision index card. Write the words in red on one side of the card and those in blue on the other side.
The Visible Spectrum Richard Of York Gave Battle In Vain
Red, Orange, Yellow, Green, Blue, Indigo, Violet.