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The Spectrum of Visible LightThe section of the electromagnetic spectrum visible to the human eye is called the visible spectrum. The electromagnetic radiation of the visible spectrum is called visible light or just light. Human eyes are sensitive to the wavelength of range from 380 to 740 nanometers. This wavelength range corresponds to a band of frequency between 405-790 THz. The visible spectrum does not contain all the colors which can be visually distinguished by the human eye. For example, unsaturated colors like pink and purple variations like magenta are absent in the visible spectrum, because these colors can only be made by a mixture of multiple wavelengths. The colors which are made up of only one wavelength are called pure colors or spectral colors. [Image to be added Soon] (White light dispersed by a prism to its constituent colors of the visible spectrum.) The Electromagnetic Spectrum Visible LightElectromagnetic waves can travel through space or vacuum. Mechanical waves require a material medium in order to transport energy, whereas electromagnetic waves can transport energy through the vacuum of outer space.
The subdivision of the electromagnetic spectrum into smaller spectra is done based on how the electromagnetic waves of each region interact with matter. What is the Visible Spectrum of Light?Electromagnetic waves exist in a wide range of wavelengths and frequencies, but our eyes are sensitive only to the narrow band of wavelengths & frequencies. This narrow band of wavelengths is the visible spectrum or the visible light spectrum. Light is an electromagnetic wave, by which we are able to see. Visible light or visible spectrum is a small part of the electromagnetic spectrum. The visible light consists of a spectrum of wavelength ranging from 400 nanometers to 700 nanometers. More familiarly, the range of wavelength is expressed as 7 × 10-7 meters to 4 × 10-7 meters. The narrow band of visible light is also called VIBGYOR. Wavelength and Color Spectrum ChartThe wavelength of electromagnetic radiation is related to the frequency and energy, and it determines the color of the radiation. The wavelength range of different colors is mentioned in the list below. The boundaries of these wavelengths in the electromagnetic spectrum are not separated drastically, but they blend with each other. One edge of the visible light spectrum has the ultraviolet region, while the other edge has infrared radiations.
The visible portion of the electromagnetic spectrum is [Image to be added Soon] Each wavelength of the spectrum of visible light represents a particular color. This is why, when the light of that particular wavelength strikes the retina of our eye, we see that particular color. Sir Isaac Newton showed that when white light is passed through a prism, it gets separated in its constituent colors of different wavelengths. This proves that the visible light is composed of various colors. The separation of visible light into its constituent colors of different wavelengths is known as dispersion. Every color has the characteristic of a distinct wavelength and light of different wavelength bends with different angles when it passes through a prism. For these reasons, the individual colors of visible light are dispersed when it is passed through a prism. Dispersion of White Light through a Prism Produces the Following Colors Violet (V) Indigo (I) Blue (B) Green (G) Yellow (Y) Orange (O), and Red R. For this reason; visible light is also called VIBGYOR. The red color of light has the longest wavelength among the visible spectrum, while the violet color of light has the shortest wavelength. Within red & violet, there is a continuous range of wavelengths. Below is the diagram of the visible light spectrum, showing the constituent colors of the spectrum. [Image to be added Soon] Which color of the visible light spectrum has the highest frequencyThe diagram below shows the regions of the electromagnetic spectrum. The longer the wavelength, the lower is the frequency, as wavelength and frequency are inversely proportional to each other. The long-wavelength regions are located on the left side of the spectrum, whereas the shorter wavelength regions are located on the right side of the spectrum. The visible light area & X-ray region are two narrow regions of the spectrum. [Image to be added Soon] |