Between the Most relevant characteristics of light They emphasize its electromagnetic nature, its linear character, which has an area that is impossible to perceive for the human eye, and the fact that, within it, all the colors that exist can be found.
The Electromagnetic nature It is not exclusive to light. This is one of many other forms of electromagnetic radiation that exist. Microwave waves, radio waves, infrared radiation, X-rays, among others, are forms of electromagnetic radiation.
Many scholars devoted their lives to understanding light, defining its characteristics and properties, and investigating all its applications in life.
Galileo Galilei , Olaf Roemer, Isaac Newton , Christian Huygens, Francesco Maria Grimaldi, Thomas Young, Augustin Fresnel, Siméon Denis Poisson and James Maxwell are just some of the scientists who throughout their history have dedicated their efforts to understand this phenomenon and to recognize all its implications.
10 main features of light
1- It is undulatory and corpuscular
They are two great models that have been used historically to explain what the nature of light is.
After several investigations, it has been determined that light is both wave-like (because it propagates through waves) and corpuscular (because it is made up of tiny particles called photons).
Different experiments in the area revealed that both notions could explain the different properties of light.
This leads to the conclusion that the wave and corpuscular models are complementary, not exclusive.
2- It spreads in a straight line
Light carries a straight direction in its propagation. The shadows generated by the light in its path, are evident evidences of this characteristic.
The theory of relativity, proposed by Albert Einstein in 1905, introduced a new element in affirming that in space-time, light shifts in curves as it is diverted by elements that stand in its way.
3- Finite speed
The light has a speed that is finite and can be extremely fast. In the void, it can travel at about 300,000 km / s.
When the area in which the light is displaced is different from the vacuum, the speed of its displacement will depend on the conditions of the environment that affect its electromagnetic nature.
4- Frequency
The waves move in cycles, ie they move from one polarity to the next and then return. The characteristic of the frequency has to do with the number of cycles that occur in a given time.
It is the frequency of light that determines the level of energy of a body: at higher frequency, higher energy; At lower frequency, lower energy.
5- Wavelength
This characteristic has to do with the distance that exists between points of two consecutive waves that occur in a certain time.
The value of the wavelength is generated from the division between the speed of the waves between the frequency: the shorter the wavelength, the frequency will be higher; And the longer the wavelength, the lower the frequency.
6- Absorption
The wavelength and frequency allow the waves to have a specific pitch. The electromagnetic spectrum contains within it all possible colors.
Objects absorb the waves of light that impinge upon them, and those that do not absorb are those that are perceived as color.
The electromagnetic spectrum has a visible area for the human eye, and another that is not. Within the visible area, ranging from 700 nanometers (red color) to 400 nanometers (violet color), different colors can be found. In the non-visible area, for example, infrared rays can be found.
7- Reflection
This feature has to do with the fact that light is able to change direction when reflected in an area.
This property indicates that, when the light strikes a smooth surface object, the angle at which it will reflect will correspond to the same one that had the ray of light that first affected the surface.
Looking at yourself in a mirror is the classic example of this feature: light is reflected in the mirror and originates the image that is perceived.
8- Refraction
The refraction of light is related to the following: in its course, the light waves can cross transparent surfaces perfectly.
When this happens, the speed of movement of the waves is reduced and this causes the light to change direction, which generates a bending effect.
An example of refraction of light can be placing a pencil inside a glass with water: the broken effect that is generated is the result of the refraction of light.
9- Diffraction
The diffraction of light is the change in the direction of waves as they pass through apertures, or when they surround an obstacle in their path.
This phenomenon occurs in different types of waves; For example, if one observes the waves generated by sound, diffraction can be noticed when people are able to perceive a noise even when it comes from, for example, from behind a street.
Although the light travels in a straight line, as already seen above, the characteristic of diffraction can also be observed, but only in relation to objects and particles with very small wavelengths.
10- Dispersion
The dispersion is the ability of the light to separate as it passes through a transparent surface, and to show as a consequence all the colors that are part of it.
This phenomenon occurs because the wavelengths that are part of a beam of light are slightly different from each other; Then each wavelength will form a slightly different angle as it traverses a transparent surface.
Dispersion is a feature of lights having various wavelengths. The clearest example of the scattering of light is the rainbow.
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