Colours of the visible spectrum
Light that is a mixture of all the frequencies of visible light, so it appears white. can be split up to form a spectrum using a prism. This is a block of glass with a triangular cross section.
Watch this video for an explanation of the visible spectrum.
The light waves are Process by which a wave changes speed and sometimes direction upon entering a denser or less dense medium, eg a light ray changes direction when refracted by a lens. as they enter and leave the prism. The shorter the The length of a single wave, measured from one wave peak to the next. of the light, the more it is refracted. As a result, red light is refracted the least and violet light is refracted the most - causing the coloured light to spread out to form a spectrum. This is called Spreading out of the different wavelengths of light, caused by refraction of light as it passes through a prism..
