The first thing we must understand is that Ultraviolet radiation is a type of light.
What? Really? You might ask.

The thing is, LIGHT, as science knows it, goes way beyond what your eyes can see. Humans have developed eyes that can sense what is known as Visible Light, which is basically all the colour shades from Red to Violet that we can see.
Wait, wait…how about white ? Or black? Aren’t they colours too?
Well, putting simply and without going into detail white light is the combination of all those colour shades you know and pure black is simply the absence of colour (therefore, not a colour). Click here for further details.
Anyway, Ultraviolet light is part of what we know as the Electromagnetic Spectrum, of which Visible light is also a part of. The electromagnetic spectrum is just a name that scientists give to the types of radiation when they want to talk about them as a group. Radiation is energy that can travel in space and spreads out as it goes.
Ultraviolet Radiation, on the other hand, has a higher frequency (and a smaller wavelength) than visible light, so it has more energy. The higher the frequency, the more energy it has and therefore, the more dangerous it can be.
The Anatomy of a wave

Frequency is the number of waves that pass through a certain point in one second







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