How much of the electromagnetic spectrum in contained in white light?

Answer 1

The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation.[1] The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object. The electromagnetic spectrum extends from below frequencies used for modern radio through to gamma radiation at the short-wavelength end, covering wavelengths from thousands of kilometers down to a fraction of the size of an atom. The long wavelength limit is the size of the universe itself, while it is thought that the short wavelength limit is in the vicinity of the Planck length, although in principle the spectrum is infinite and continuous. EM radiation with a wavelength between 380 nm and 760 nm (790-400 terahertz) is detected by the human eye and perceived as visible light. So only a very small portion of the entire spectrum is visible.