We explain what light energy is, its advantages, disadvantages, uses and other characteristics. Also, how to obtain it and examples.
What is light energy?
Light energy or luminous energy is the energy carried and composed by light waves. Therefore, to understand what we mean by this type of energy, we must first know what we call light.
Light is a type of electromagnetic radiationcomposed of particles called photons. It is located within a band of the electromagnetic spectrum that our eyes are capable of detecting. Visible light is between the infrared and ultraviolet areas of the spectrum, it has a particular range of frequencies, wavelengths and energies.
Light is transmitted through materials or even in a vacuum, as it is a form of radiation. The elementary particle associated with light is called a photon and as such behaves both as matter and as a wave.
Light energy is intimately related to the amount of visible light considered in a situationtaking care to differentiate it from radiant energy, which includes other electromagnetic radiation of frequencies that are imperceptible to the human eye, such as X-rays, for example.
The branch of science responsible for studying the relationship between light and the visual system is photometry.
See also: Chemical energy
Characteristics of light energy
Light energy is represented by the symbol Qv. In physics it is expressed in lumens per second (lm.s), since it is defined as the light flux at a given time t (Qv = F . t).
Its interaction with objects occurs in material terms, and always depends on the physical-chemical properties of the illuminated object, as well as the geometric orientation with which the light impacts it. So, Some objects absorb light energy and others partially reflect itwhich precisely explains the appearance of the colors that the human eye can capture.
How is light energy obtained?
Light energy is always obtained from light and, therefore, can be generated naturally or artificially, through various means.
- Naturally. Light energy is the product of certain types of exoenergetic chemical reactions, that is, those that release energy, like those that take place within stars, such as the Sun. In fact, the Sun is our great source of daily light energy.
- artificially. Light energy can be generated through different physical-chemical mechanisms, such as combustion, or also through electricity, just as we do every day when turning on a light bulb.
Advantages and disadvantages of light energy
Light energy is particularly necessary since allows us to see and differentiate the reality around us. On the other hand, it is possible to give it practical uses through various mechanisms and technologies.
For example, photovoltaic cells convert it into electricity and the night lighting that we have used for thousands of years makes us less dependent on the Sun. More recently, cinema and photography made it possible to capture light in photosensitive substances.
Light energy cannot be created from nothing, always requires a light sourceso it cannot occur spontaneously.
Uses and applications of light energy
Some of the uses of light energy are:
- Maintain illuminated environments when the sun has fallen, or when sunlight does not have access to them.
- Project and capture images on films and sensitive surfaces, such as in photography or cinema.
- Through concentrators, this energy can be used to generate other types of energyas in solar panels or in the classic case of burning a leaf with a magnifying glass.
Examples of light energy
The Sun is the largest source of light energy that we know of. It is a huge mass of atoms in space, which interact through nuclear reactions generating heat, light energy and many other forms of radiation. The light energy of the Sun illuminates the planet and provides it with heatwhich is key to climate stability and the perpetuation of life.
Other possible examples of light energy are found when turning on a lamp, a lanternor any similar device.
Continue with: Electrical energy
References
- “Light energy” on Wikipedia.
- “Light energy” in Natural Sciences.
- “Types of energy” (video) in Aula365.
- “The world of energy” in Gasco Educa (Chile).
- “Light” in The Encyclopaedia Britannica.
