Light Study, Properties And Characteristics

0 / 5. 0

Light study, properties and characteristics

 

Optics is the part of physics that deals with the study of light and its phenomena. We can find several authors who define the light in different ways. The precursor of these studies was Newton, which defined the light as a stream of particles from a source that produced a sense of vision when entering the eye. According to Maxwell and Hertz, light is a wave that does not need material support to spread since it spreads transversely.

Light is a form of energy that originates in light objects and that is transmitted by vacuum and transparent media (bodies that let the light pass and can be seen through them). These luminous bodies emit a fraction of energy that reaches our eyes, thus causing the vision, which is the feeling that the light produces when it reaches us. This book concludes that light is the link between the world of living beings and the inanimate.

Another author who tells us about light is Tipler P. A., defining it as electromagnetic waves with undulatory movement. It also explains that light has double nature, that is, according to Tipler, light behaves as a matter in motion, it has corpuscular nature and as a marching wave associated with matter.

Properties

The light is transmitted in several ways. In addition, it has several properties, one of them is the rectilinear propagation, each direction that takes the light is called Luminous Ray.

If the light were not in a straight line those waves could surround the objects that were found in their path and there would be no shadow. When a luminous focus is projected in a plane, three parts can be distinguished: the gloom, the area that is illuminated and the shadow. The gloom is the area where only some rays arrive. The illuminated area perceives all the rays of light. The shadow is the part that does not receive light. When the shadow is more elongated, the greater the angle that forms the lightning light with the surface on which it is projected.

When a lightning light reaches an area of two different means, it is reflected or bounces. This characteristic of light is called light reflection. The ray that reaches the surface is called Rayo incident, and the lightning that is bounced is called reflected ray. The incident angle of the light ray will coincide with the reflected angle.

On polished surfaces as mirrors are totally or partially reflected. And if this is a flat surface the shape of the images will be the same in form and size as the real object. But when the surface is curved, concave or convex, they have a wide field of vision, but the images will be smaller than the real ones. The clearest example is known to the rearview car of a car.

The dispersion of the light occurs when a lightning is refracted in some means and its colors remain, as in the rainbow when it rains, the sunlight (white) affects the drops separating the colors, since each one has adifferent frequency. Even that the human eye cannot see, which is the darkest and most warm, infrared, it has a higher wave. On the contrary, which has a shorter wavelength than the violet is called ultraviolet. Electromagnetic waves: typical transverse waves, in addition to rope waves.

Wave frequency

"The frequency is the number of vibrations that are made in the time unit or the number of cycles per second" 

Wave intensity.

“The intensity of any wave is the energy per unit of area, per unit of time;In practice, it is the average power transported by the wave through a unitary area perpendicular to the direction of wave propagation. Assume that in a time an amount of energy crosses the area that is perpendicular to the wave propagation direction ”.

Wave speed

“Speed is a vector amount that covers the speed and direction of the movement. If an object experiences a vector displacement in a time interval ”.

“The direction of the vector vector is the same as that of the vector displacement. The units of speed (and speed) are those of the distance divided by the time, such as m/s or km/h ”.

“The instantaneous speed is the average speed evaluated for a time interval that tends to zero. Therefore, if an object is subjected to a displacement in a time, the instantaneous speed for that object is where the notation means that the reason is going to be evaluated for a time interval that tends to zero ”.

Wavelength

"In the sound waves the vibration direction is parallel to the propagation direction".

Characteristic

The particularity of the light is that it spreads both in a straight line and in all directions, in addition to a speed of 300.000 km/sec: That’s why a light year is equivalent to the distance that runs the light in a year (10 bill of km).

Electromagnetic spectrum of light

In Newton studies reflected in the Tipler P book. A. We see that he was the first to realize that white light is a mixture of light that contains all colors, of approximately equal intensity. For this study he used a glass prism.

Electromagnetic energy is the energy that lies in the interaction of electric and magnetic fields.

The spectrum of light is a set of energies. Within this spectrum we find the visible light, that is, the light we perceive with the eyes. This visible spectrum is a very narrow strip of electromagnetic energy that covers a wavelength from 4.000 to 7.000. The values covered by the previous ones are called infrared rays and those that are positioned in a higher frequency are ultraviolet rays.

We can distinguish two types of radiation: those that are present in nature and those that are artificial. Within these two types, radiation is divided into two categories:

Ionizing radiation that is high frequency and can cause damage to cells. Here we would find: gamma rays, radiographs, UV rays (high energy) microwaves and subatomic particles radio waves.

Non -ionizing radiation that is low frequency and is not considered a cause of cancer, except in the case of UV rays. Here we would find: UV rays (low energy), visible light and infrared rays.

Only wavelengths associated with the visible region can affect the human eye, producing color perception. We call these wavelengths "light". The visible region of the spectrum comprises a range of wavelengths that go from the 350 nm that is the violet color, to the 800 nm that is the red color. The ultraviolet (UV) and infrared (IR) regions fall on both sides of the visible region.

Based on Tipler P. A. The spectrum involves the undulating propagation of electric and magnetic fields in space with a speed of 3x 〖10〗^8 m/s in a vacuum. These electromagnetic waves are originally from the acceleration of electrical loads and to differentiate the types of electromagnetic waves we must look at their frequency and wavelength. Tipler p. A. He explains that our human eye is sensitive to electromagnetic radiation of wavelength called visible light, that is, the one between 4x 〖10〗^(-7) m and 7x 〖10〗^(-7) approximately approximately.

Finally Garcia e. (2007) helps us complement the spectrum of light by adding that objects appear with color when they have the property of absorbing light a certain wavelength and reflecting the rest. In addition, the white light occurs when all the wavelengths of the visible spectrum are of equal proportion and intensity.

UV rays: according to Tipler P. A. The ultraviolet light are wavelengths beyond the visible margin and is an electromagnetic radiation that is a bit distant from the shortest wavelength part of the visible interval. The UV rays closest to the visible interval are less dangerous, and they are the ones that originates the sun. UV rays closest to gamma rays are more dangerous and can cause death because they ionize our cells and when we remove electrons we produce anomalies.

Reflection of light

Reflection is a phenomenon that appears when there is a small deviation from the online trajectory of light. This change of direction occurs when a ray of light travels through a transparent medium and changes to another diaphanous medium. An issue that we can highlight is that the speed that light has in a vacuum has a faster than when traveling in any other means.

From this issue that we have just highlighted we must talk about the refractive index, which is a measure in which we can know the reduction of the speed suffered by the light caused by the change of the environment on which it spreads

The reflection of the light is defined as a phenomenon appears when a ray of light that moves in a medium finds a limit that is directed to a second medium, a part or the full lightning is reflected in the first medium.

It also states that there are various types of reflection in which the type of surface in which they are reflected influences. These types of reflection are as follows:

Specular or regular reflection

Specular reflection as a phenomenon occurs when the surface on which it is reflected has the peculiarity of being smooth or polished, that is, without having a rough character and thus gives rise to a reflection of light towards a single direction. You could say that this polished surface acts as a mirror reflecting the light.

In this reflection you have to make a small nuance to clarify some basic concepts such as incident rays and rays reflected in which incident rays are those that are emitted from a point and the reflected rays, their own word defines it, are the raysthat have suffered the phenomenon of reflection and therefore reflect on another point)

Diffuse reflection

It also states that if the surface has a rough or irregular character, the incident beam is reflected towards all directions because the wall does not have a uniform structure, that is, having the peculiarity of lacking a smooth surface in whichProject, the reflected ray is dispersed in all directions.

Total internal reflection

This type of reflection is characterized by the fact that the light that occurs will be reflected in the inside of the medium with a greater refraction index. This reflection is guided by the same laws that the reflection of light is governed, which, citing Euclids are:

“Law 1. The incident and reflected ray is in the same plane.

Law 2. The angle with which lightning has a surface is the same as the angle that forms with it the reflected ray."

Propagation/ Light Transmission

There are several ways in which the light can be transmitted from one medium to a different medium. These forms are as follows:

  • Simple dispersion: it can also be called "dispersion by a single obstacle" and can be explained as follows. The electromagnetic field polarizes an obstacle. Due to this polarization, a new electromagnetic field is created both in the polarized and around it.
  •  Coherent retrodispersion: In this form of propagation of light, the waves move along their trajectory in opposite senses, that is, these waves interfere with each other and hinder the construction of light. In other words, we could raise the idea that a wave can return to its point of origin after spreading along the trajectory in that medium.

Diffraction

The phenomenon of the diffraction of the light, happens at the edge of the obstacles that the light is found when it spreads, and is diverted or dispersed. It is a characteristic undulatory movement that is explained by the Huygons principle, which it says;that each point on a wavefront that progresses, can be considered a new wave or secondary wave, which combine.

Diffraction refers to the deviation of the propagation in a straight line that occurs when a wave passes to the other side of a partial obstruction. It usually corresponds to the bending or dispersion of the waves around the banks of an opening and obstacles. The simplest form of light diffraction is that of the distant field or diffraction fraunhofer. It is observed on a screen that is distant from the opening or obstacle that obstructs an incident flow of flat waves. The diffraction puts a limit in the size of the details that can be observed optically ’.

Refraction

According to Garcia, it is a phenomenon that happens when a ray of light diverts its trajectory by crossing a separation surface "between different means according to the refraction law". This happens because the light spread at different speed in each of them. That is, it is the change of direction that suffers a ray of light when moving from a transparent medium to another that has a different density.

Displacement degrees:

  • It is the deviation of the incident ray with respect to the normal when it has been refracted. It depends so much on the density of the substances, the angle on which it is influenced and the incident ray wavelength.
  • When the light passes from one means of propagation to another, it undergoes a change of speed that accompanies, if it does not enter perpendicularly, a change of direction in its trajectory, due to the different speed of propagation that the light has in the different materials ”.

In summary, the refraction is the deviation of the rays of light when they pass from one medium to another, since when the rays go by the same medium (air), they go straight, however, when it changes half (liquid), it isThey begin to divert.

At what point is this deviation from the rays of light? 

This point is what is known as focal point, that is, the distance between the optical center of the lens and the focus.

Decomposition of white light

White light like that which comes directly from the sun, which can be broken down into strips of colors that we call rainbow. The white light is formed by a range of wavelengths, where each corresponds to a color, which goes from red to violet.

When this light crosses an object, it forces the different waves that form the white light to move at different speeds, obtaining as a result the visible spectrum of white light or rainbow.

This decomposition begins to study at the S.XVIII, due to the philosopher, astronomer and mathematician Isaac Newton, who in 1666 began to perform experiments on colors, passing a prism a ray of light. Newton appointed spectrum to the ordination of colors from violet to red. Through the realization of different experiments, he concluded his idea that the white light is formed by colors, where each color is associated with a specific wavelength.

Therefore, if a sunbeam or white light crosses a glass, it is observed how this light decomposes and separates in lights of different colors;Like red, yellow, orange, blue, violet and green.

We can conclude that the white light is formed with all the colors named, by penetrating the colors in the glass, each color has a different deviation, so the beam of light penetrates the glass is shown in a multicolored way.

The process that the white light separates in different colors we call it, decomposition of light.

conclusion

As a summary of this work, we have learned the importance of light because it is responsible for detecting objects, as well as the existence of objects that do not allow light to pass through them.

Technically, we can define light as all electromagnetic radiation capable of being perceived by our sense of sight, while visible light specifically indicates radiation in the visible spectrum. Within its characteristics we highlight that it is an electromagnetic wave of high frequency composed of particles without mass, which contain energy, being a manifestation of this. A phenomenon that happens when a beam of light clashes with the surface based on the light beam again spread through the same medium, but in another direction. When the surface is smooth, we will call specular reflection, however if the surface is irregular, diffuse reflection.

Finally we define the white light as the composition of different colors, moving each of them by moving at different speeds, wavelengths and using different amounts of energy.

Free Light Study, Properties And Characteristics Essay Sample

Related samples

Zika virus: Transmission form Introduction The Zika virus belongs to the Flaviviradae family, was found for the first time in a monkey called Rhesus febrile and in...

Zika virus: cases and prevention Introduction The World Health Organization (WHO) has confirmed that Zika is a virus caused through the mosquito bite which is...

Zeus The King of Greek mythology Introduction Zeus is the Olympic God of heaven and thunder, the king of all other gods and men and, consequently, the main figure...

Zeus's punishment to Prometheus Introduction Prometheus, punished by Zeus Prometheus, punished by Zeus. Prometheus is a ‘cousin’ of Zeus. He is the son of the...

Comments

Leave feedback

Your email address will not be published. Required fields are marked *