The Electromagnetic Spectrum Visible Light

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The Spectrum of Visible Light

The 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.

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(White light dispersed by a prism to its constituent colors of the visible spectrum.)

The Electromagnetic Spectrum Visible Light

Electromagnetic 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. 

  • Electromagnetic waves are produced by vibrating electric and magnetic charges, and hence they are composed of both electric and magnetic components.

  • Electromagnetic waves exist over a wide range of wavelengths, and frequencies with a continuous range of frequencies called the electromagnetic spectrum. This entire range of the spectrum is broken down into small specific parts. 

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 Chart

The 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.

Color

Wavelength (nm)

Violet

380 - 435

Indigo

435 - 500

Blue

500 - 520

Green

520 - 565

Yellow

565 - 590

Orange

590 - 625

Red

625 - 740


The visible portion of the electromagnetic spectrum is

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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.

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Which color of the visible light spectrum has the highest frequency

The 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.

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FAQ (Frequently Asked Questions)

Q1. How much of the Electromagnetic Spectrum is Made up of Visible Light?

Ans- The entire observable visible light spectrum makes up a small portion of about 0.0035 percent of the electromagnetic spectrum.

The light that reaches us constitutes less than 1% of the visible spectrum. Scientists estimate that it is about 0.0035% of the total electromagnetic spectrum. 

Since the human eye is limited in its range, we are able to see only a tiny fraction of the electromagnetic spectrum.

Q2. Which Wavelengths of Electromagnetic Energy are Visible to the Human Eye?

Ans- The section of the electromagnetic spectrum perceivable to the human eye is called the visible spectrum. This range of wavelength is specifically called visible light. The range of wavelengths that the human eye can detect is from 380 to 700 nanometers.

Q3. What are Two Examples of Waves We can See?

Ans- Out of all the radiations of the electromagnetic spectrum like radio waves, x-rays, gamma rays, etc., we are able to see only the visible light like red light, green light, yellow light, blue light, and violet light.

Q4. What are the Seven Types of Waves?

Ans- The electromagnetic waves are classified into seven basic types by distributing them in terms of wavelength and frequency.

i. Radio Waves: These have the longest wavelengths and are used for instant communication.

ii. X-rays: Used to scan objects by penetrating radiation.

iii. Gamma Rays: The main purpose of this radiation is in nuclear energy.

iv. Ultraviolet Waves: These are energetic light.

v. Microwaves: used in storing data and generating heat

vi. Infrared Waves: it produces Invisible heat.

vii. Visible Light Rays:We are able to see because of visible light radiations.