Dunno but here is a good link! http://mintaka.sdsu.edu/GF/explain/optics/rendering.html
A spectrum goes from red at the low frequency end to violet at the high frequency end.
Red is at the low frequency end of the visible spectrum.
The longest visible wavelengths are thoseat the red end of the spectrum (rainbow).
The colour at the opposite end of the colour spectrum is violet.
The warm end of the visible spectrum is red, while the cool end is violet.
Red is at the top of the visible light spectrum because it has the longest wavelength of all the visible light colors. As a result, red light is located at the longer end of the spectrum, while colors like violet and blue are at the shorter end due to their shorter wavelengths.
Red light has the longest wavelength in the visible spectrum.
The wavelength of red light typically falls between 620 and 750 nanometers. It is on the longer end of the visible light spectrum.
Red (low end) & Violet (high end).
Longer.
Please phrase your question in the form of a complete sentence.
Red at one end, purple at the other.