A system needs energy to do work. There are various forms of energy that are used for different purposes. Light energy is one of those. Lives on the Earth are highly dependent on the energy of light in many aspects. Sun is the only natural source of light in Earth. We are using sunlight directly and indirectly in our daily life. In this conceptual discussion, I’m going to explain the definition, sources, properties, examples and uses of light energy.
Contents of this article:
- What is light energy?
- Sources of light
- Properties of light
- Examples of light energy
- Uses of light energy
Definition of Light Energy
If we heat a body its temperature increases and begins to glow. We can see the glowing body because it emits light in all directions in the form of electromagnetic radiation. The electromagnetic radiation emitted by a hot body propagates in the form of energy. This energy is called light energy or simply, the light.
Sources of light
Sun is the source of light and all other energies. Because all other forms of energy are the transformed forms of the light energy coming from the Sun. A hot body emits energy in the form of light. If we heat a body, it will glow at high temperature and will emit lights. Sun glows and emits a huge amount of light because of the heat generated by the nuclear fusion process inside the sun. There are some secondary sources of light which are listed below –
- An electric bulb emits light due to the heating of its filament by electrical energy. This is an example of the conversion of electrical energy into heat energy and then heat energy into light energy.
- Burning of fossil fuels generates light. This is an example of transformation of the chemical energy into light.
Properties of light energy
Light has some notable properties that are useful to understand the nature of light. Let’s have a list of those properties –
- Energy of light propagates in the form of transverse electromagnetic wave.
- It is kinetic energy that travels with a speed of 3 108 m/s.
- Light does not need any medium to propagate. It can propagate by emission process through the free space.
- Light of different colors has different wavelengths. However, the speed is the same for each colored light.
- Being a wave, the light shows reflection, refraction, polarization and diffraction phenomena.
- Light shows particle nature as well. Quantum mechanics tells us that light is made of Photon particles.
Examples of light energy
Examples of light energy means the examples where the light is transformed into another form of energy. There are plenty of examples of this.
- A bucket of water can be heated by sunlight. This is an example where light converts into heat.
- Plants produce food by photosynthesis with the help of sunlight. This is an example of the conversion of light into chemical energy.
- Solar panels or solar cells convert solar energy into electrical energy.
Uses of light energy
Sun is the source of all energy. So, we are using the energy of the sun everywhere. Here I’m trying to highlight some of the most important applications of light energy.
The basic use of light is to see an object. Humans and all animals can see because of the presence of light. We can see an object only if the light reflects on our eyes from that object. However, there is a limitation. Human can see an object only when visible light reflects from the object. Some animals can see in other light in the radiation spectrum.
To generate heat and electricity
Energy of light is used as a source of heat and electricity as well. Here is a list of some examples from our daily life –
- Heating a bucket of water.
- Drying wet cloths
- Heating our bodies in the winter season.
- Solar panels produce electricity from solar energy.
In colorful views
We can see the world as colorful because of the light. White light has seven different colors in its spectrum. The color of an object appears to be the same as that of the reflected light from that object. For example, the leaves of plants reflect green-colored light and therefore, we see the color of leaves as green.
The Quantum nature of photons is getting popularity in computation. The high speed and high degrees of parallelism make the light useful in quantum computing.
Nowadays it has become a fashion of decoration for every occasion. Lighting plays a huge role in it. Different colored light makes a night party or other occasions very eye-catching.
This is all from this article on the energy of light and its uses in our daily life. If you have any doubts on this topic you can ask me in the comment section.