- Main characteristics of the light
- 1- It is undulatory and corpuscular
- 2- It spreads in a straight line
- 3- finite speed
- 4- Frequency
- 5- Wavelength
- 6- Absorption
- 7- Reflection
- 8- Refraction
- 9- Diffraction
- 10- Dispersion
- References
Among the most relevant characteristics of light are 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 is not unique to light. This is one of the 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 dedicated their lives to understanding light, defining its characteristics and properties, and investigating all of 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 history, devoted their efforts to understanding this phenomenon and acknowledge all its implications.
Main characteristics of the 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 different investigations, it has been determined that light is, at the same time, wave (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 led to the conclusion that the wave and corpuscular models are complementary, not exclusive.
2- It spreads in a straight line
The light carries a straight direction in its propagation. The shadows generated by the light in its path are evident proof of this characteristic.
The theory of relativity, proposed by Albert Einstein in 1905, introduced a new element by stating that, in space-time, light moves in curves as it is deflected by elements that get in its way.
3- finite speed
Light has a speed that is finite and can be extremely fast. In a vacuum, it can travel up to 300,000 km / s.
When the field in which light travels is different from vacuum, the speed of its movement will depend on the environmental conditions that affect its electromagnetic nature.
4- Frequency
The waves move in cycles, that is, they move from one polarity to the next and then return. The frequency characteristic has to do with the number of cycles that occur in a given time.
It is the frequency of light that determines the energy level of a body: the higher the frequency, the higher the energy; the lower the frequency, the lower the energy.
5- Wavelength
This characteristic has to do with the distance between points of two consecutive waves that occur in a given time.
The wavelength value is generated by dividing the speed of the waves by the frequency: the shorter the wavelength, the higher the frequency; and the longer the wavelength, the lower the frequency.
6- Absorption
Wavelength and frequency allow waves to have a specific tone. The electromagnetic spectrum contains within itself all possible colors.
Objects absorb light waves that fall on them, and those that do not absorb are those that are perceived as color.
The electromagnetic spectrum has one area that is visible to the human eye, and one that is not. Within the visible area, which ranges from 700 nanometers (red color) to 400 nanometers (purple color), the different colors can be found. For example, infrared rays can be found in the non-visible area.
7- Reflection
This characteristic has to do with the fact that light is able to change direction when reflected in an area.
This property indicates that when light falls on an object with a smooth surface, the angle at which it will be reflected will correspond to the same angle as the light beam that first struck the surface.
Looking in a mirror is the classic example of this feature: light reflects off the mirror and creates the image that is perceived.
8- Refraction
The refraction of light is related to the following: light waves can pass through transparent surfaces perfectly on their way.
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 the refraction of light can be placing a pencil inside a glass of water: the broken effect that is generated is a consequence of the refraction of light.
9- Diffraction
The diffraction of light is the change in the direction of waves when they pass through openings, or when they go around an obstacle in their path.
This phenomenon occurs in different types of waves; For example, if the waves generated by sound are observed, the diffraction can be noticed when people are able to perceive a noise even when it comes, for example, from behind a street.
Although light travels in a straight line, as seen before, the diffraction characteristic can also be observed in it, but only in relation to objects and particles with very small wavelengths.
10- Dispersion
Scattering is the ability of light to separate when passing through a transparent surface, and as a consequence show all the colors that are part of it.
This phenomenon happens because the wavelengths that are part of a light beam are slightly different from each other; then each wavelength will form a slightly different angle as it passes through a transparent surface.
Scattering is a characteristic of lights that have various wavelengths. The clearest example of light scattering is the rainbow.
References
- "The nature of light" in Virtual Museum of Science. Retrieved on July 25, 2017 from the Virtual Museum of Science: museovirtual.csic.es.
- "Characteristics of Light" in CliffsNotes. Retrieved on July 25, 2017 from CliffsNotes: cliffsnotes.com.
- "Light" in Encyclopedia Britannica. Retrieved on July 25, 2017 from Encyclopedia Britannica: britannica.com.
- Lucas, J. "What Is Visible Light?" (April 30, 2015) in Live Science. Retrieved on July 25, 2017 from Live Science: livescience.com.
- Lucas, J. "Mirror Image: Reflection and Refraction of Light" (October 1, 2014) in Live Science. Retrieved on July 25, 2017 from Live Science: livescience.com.
- Bachiller, R. “1915. And Einstein bent the light ”(23 November 2015) in El Mundo. Retrieved on July 25, 2017 from El Mundo: elmundo.es.
- Bachiller, R. "Light is a wave!" (16 September 2015) in El Mundo. Retrieved on July 25, 2017 from El Mundo: elmundo.es.
- "Colors of light" (April 4, 2012) in Science Learning Hub. Retrieved on July 25, 2017 from Science Learning Hub: sciencelearn.org.nz.
- "Light: electromagnetic waves, electromagnetic spectrum and photons" in Khan Academy. Retrieved on July 25, 2017 from Khan Academy: es.khanacademy.org.
- "Wavelength" in Encyclopedia Britannica. Retrieved on July 25, 2017 from Encyclopedia Britannica: britannica.com.
- "Frequency" in Encyclopedia Britannica. Retrieved on July 25, 2017 from Encyclopedia Britannica: britannica.com.
- "Light scattering" in FisicaLab. Retrieved on July 25, 2017 from FisicaLab: fisicalab.com.
- "Dispersion of Light by Prisms" in The Physics Classroom. Retrieved on July 25, 2017 from The Physics Classroom: physicsclassroom.com.
- "Reflection, Refraction, and Diffraction" in The Physics Classroom. Retrieved on July 25, 2017 from The Physics Classroom: physicsclassroom.com.
- Cartwright, J. "Light Bends by Itself" (April 19, 2012) in Science. Retrieved on July 25, 2017 from Science: sciencemag.org.