Visible light

Radio signals, infrared radiation, visible light, ultraviolet radiation, X-rays, and microwaves are all examples of electromagnetic (EM) radiation. Visible light is defined as the wavelengths that are accessible to the majority of human eyes.

Visible light

The Radio waves, infrared radiation, visible light, ultraviolet radiation, X-rays, and microwaves are all examples of electromagnetic (EM) radiation

The wavelengths of visible light span from 400 nm to 700 nm, with a frequency range of 400 THz- 800 THz. This is the portion of the electromagnetic spectrum that the human eye can “see” and distinguish optically. If white light passes through the prism, it splits into the visible light spectrum’s seven colours. A natural visible light source, such as the Sun, is an example.

Colour

Colour is perhaps the most essential feature of visible light. Colour is both a characteristic of light and a human perception artefact. According to Glenn Elert, author of the physics hypertext book, objects do not “have” colour. Instead, they emit light that “appears” to be coloured. In other words, colour, according to elert, only exists in the mind of the beholder

Our eyes have specialised cells called cones that operate as receivers tuned to the wavelengths of this small region of the electromagnetic spectrum. Light at lower end of visible spectrum, with a longer wavelength of about 740 nm, is perceived as red light in middle of spectrum, with a wavelength of about 380 nm, is perceived as green; and light at the higher end, with a wavelength of 380 nm is perceived as violet. All other colours we see are a combination of these two. 

Yellow is a mix of red and green; cyan is a mix of green and blue; and magenta is a mix of red and blue. All colours are mixed together under white light. The absence of light is defined as black. Newton was the first to understand that white light was made up of the rainbow hues when he transmitted sunlight through a tiny slit and then a prism to project the coloured spectrum onto a wall in 1666. The spectrum of electromagnetic radiation that can be perceived by the human eye is known as visible light. The wavelengths in this range are between 380 and 750 nanometers (nm), and the frequency range is between 430 and 750 terahertz (THz). Between the infrared and ultraviolet ends of the electromagnetic spectrum comes the visible spectrum. Infrared radiation, microwaves, and radio waves have a lower frequency as well as a longer wavelength than visible light, but ultraviolet light, x-rays, and gamma radiation have a higher frequency and a shorter wavelength.

Colour and temperature

As objects become hotter, they emit energy with shorter wavelengths, which humans experience as shifting colours. The flame of a blowtorch, for example, changes colour from reddish to blue as it is adjusted to burn hotter. According to the Institute for Dynamic Educational Advancement’s website, WebExhibits.org, this process of converting heat energy into light energy is known as incandescence.

When hot matter releases a portion of its thermal vibration energy as photons, incandescent light is created. The energy radiated by an object enters the infrared at roughly 800 degrees Celsius (1,472 degrees Fahrenheit). The energy flows into the visible spectrum as the temperature rises, giving the object a reddish glow.

Visible light astronomy

The hue of hot objects, such as stars, can be used to measure their temperatures. The surface temperature of the sun, for example, is around 5,800 Kelvin (9,980 F or 5,527 C). The peak wavelength of the light released is around 550 nm, which we perceive as visible white light (or slightly yellowish).

The sun’s surface temperature would be reddish, similar to the star Betelgeuse, if it were around 3,000 degrees Celsius cooler. If it were hotter, at 12,000 C, it would appear blue, like the star Rigel.

Astronomers can also find out what materials objects are made of by looking at the absorption spectrum, which shows how each element absorbs light at different wavelengths. Understanding the absorption spectra of elements allows astronomers to determine the chemical makeup of stars, dust clouds, and other distant objects using spectroscopes.

Visible light uses and applications

In the modern world, this is the primary and most important application of visible light. There are lights such as an electric bulb, fireworks, and other sources of light rays that allow us to view objects and make a dark room visible with their gleaming rays.

A beam of laser light is made up of a collection of light or a concrete of light that is then pronounced. In surgery rooms, laser lights are employed because the rays make it easier for a surgeon to see and perform his tasks. Laser surgery is another type of surgery that is used to cut tissues.

Visible light makes up the waves of light that make up the television that we use to have fun and watch videos. We wouldn’t be able to focus our eyes on the TV or watch movies or other forms of entertainment if there was no visible light.

Conclusion 

Radio waves, infrared radiation, visible light, ultraviolet radiation, X-rays, and microwaves are all examples of electromagnetic (EM) radiation. The wavelengths of visible light span from 400 nm to 700 nm, with a frequency range of 400 THz- 800 THz. This is the portion of the electromagnetic spectrum that the human eye can “see” and distinguish optically. Colour is perhaps the most essential feature of visible light. When hot matter releases a portion of its thermal vibration energy as photons, incandescent light is created