Hello Steemit people and friends, I have already introduced myself, as I said in my presentation I am a scientific person and explaining physics is one of my favorite hobbies. As you know in my career we are taught to see life differently , to be curious about physical phenomena or of nature. That is why today I bring you a post that you will like, is a post that will show you that life is not what we think and that there are many things we do not understand and when we understand everything in our lives changes ... in this post I will introduce you As we are able to see the colors and I will show in this post that in fact the color of the objects is not what we think and we will understand how this one is produced physically. So to start this post I will tell you about the light, since later you will understand that the color of the objects is related to light and something called photons or in other words we will get to know because the apple is red...
To begin we must know that it is light and how we can know that when we speak of light we are referring to a determinate form, later it will be understood because we started talking about light ... In this case we must speak of something called wave. These waves if we define it physically it is only the perturbation in a certain medium and if these waves have a movement of van and see (oscillations) of equal and opposite form like the movement of the pendulum of an old clock these waves are called harmonic waves u Wave sine waves. A beautiful example of a wave is when a rock falls in the middle of a pond and we can see how the fall of that rock generates a disturbance, that perturbation is known as wave (in this case they are known as longitudinal waves).
Source:
Where the longitudinal waves are those where the movement in which the wave propagates is in the same direction of the movement of the swing of the waves ... for example the movement of the propagation of the wave is forward and the swinging motion of the wave Is forward and backward (in other words the wave motion is parallel to the wave propagation motion) ... some examples of longitudinal waves are sound, the waves produced in a water pond and sound or sonic waves .. .
Source: http://pa1.narvii.com
In an opposite case, another type of wave is known as a transverse wave, which is where the propagation of the wave is perpendicular to its reciprocating motion (in other words the wave motion is in the same direction as the wave propagation). Itself). Among these we can find the movement on a guitar string, in this case light ..
Source: http://laplace.us.es
Then we find that light has a wave behavior in this case transverse wave ... we can say that light is a wave that is produced by electric charges in movements, producing changes changes in magnetic field and electric fields ... as you can see the movement Of the wave is perpendicular to the wave motion of the wave and therefore it is said that light is a transverse wave
Source: http://www.positivehealth.com
Knowing that light is a transverse wave we must know what characteristic have this type of wave ... we will study a transverse wave and its main characteristics ...
Source: http://hyperphysics.phy-astr.gsu.edu
The main characteristics of this wave are its wavelength, amplitude, frequency and period .. that is, we can study the movement of oscillation or wave the 4 previous values are very important to study, but the deepest study of the waves would be Study reason of another post.
But the most important parameter for him studies light in the known as wavelength (that is the distance in cm of one of a whole cycle of oscillation ie complete when a full swing) therefore that distances can change and by So that distance gives the properties of the wave, in the case of sound gives the different tones in the music as bass or treble, in the case of electromagnetic waves will give its application in the case of short lengths are used in technology Current for the transmission of information in telephony ... in the case of white light each wavelength will give us the corresponding color.
Source: http://info-radiofrecuencia.es/
The previous image shows the different properties of the wave depending on its wavelength ..
Now let's talk about light ... as we know light is an electromagnetic wave that is also transverse, but what happens with white light that comes from the sun and how it is able to show the color of objects .. Let's study a little history ... In the years 1705 Isaac Newton realized an experiment using a triangular prism showing that the white light was a compound of several colors, that is to say passing white light by the triangular prime this one was decomposed in light of several colors ... this experiment showed that the light Was shaped colors which today it is known that these colors are related to the wavelength and each wavelength is related to a color.
Source: https://www.portalastronomico.com
An example of nature about the premiums and the color of light, is the famous rainbow that occurs in rainy weather, where water droplets act as premiums causing the decomposition of light in colors and forming the rainbow ...
Source : http://3.bp.blogspot.com
But before proceeding it is only necessary to know that electromagnetic waves are composed of photons, to explain in a simple way, the photon is a particle that when being in a group forms an electromagnetic wave or otherwise the electromagnetic wave is formed by photons. The photons also behaves as a wave ie it possesses the wave properties and therefore its photon behavior is equal to that of the electromagnetic wave.
The light being a transverse electromagnetic wave, besides having colors that are related to the wavelength and also a composition of photons, we would only be able to know how this relates to the color of the objects.
Recall that everything in this universe is made of matter and that these are formed by atoms, where these atoms can be considered as a planetary system or solar system as shown in the figure
Source: http://4.bp.blogspot.com
Where at the center of the atom are the protons (positive charges) is known as nucleus and the particles spinning around the nucleus are known as electrons (negative charges) and these are those involved in the interaction of light ... where each electron possesses a Energy level determined and unique ... as shown in the image
Source: http://www.monografias.com
Then when the light or photon interacts with an electron of the atom it provides energy to the electron, if the energy supplied to the electron is greater than or equal to the next level, the electron passes to the next level, where the photon is absorbed and this in physics Known as light absorption ...
but if on the other hand the energy of light is less than the next level this happens as if it had never happened there, then it is known as light reflection, in theory it is a little more complicated .. but for ease it will be explained in this way. Knowing how light interacts with objects we can come to the following conclusion ... when white light (set of all colors) reaches the object, it interacts with the electrons inside the objects and those colors with energy (photons) with length Waves greater than or equal to the next energy level of the electron are then absorbed by the object and that or those that have lower energy at those energy levels are reflected.
In other words an object like an apple the white light upon striking it, all the colors that make up the light are absorbed by the apple but the red that is reflected and therefore we see the apple of red color ... but as we have Spoken of wavelength, when interacting with the electrons we have referred to energy and the following equation relates the energy to the wavelength ...
E= hc/λ
But it is worth remembering that the interaction of photons and matter is related to the type of atom that is composed of the object ...
Source: http://2.bp.blogspot.com
In conclusion we come to something very important about the color of the objects .. We thought that color is something proper to matter, that is to say something that depended on the object and that could sprout from it without any other disturbance, but now knowing how it occurs Physically we see something very different. Since the color is only the reflection the light that is not absorbed by the object.
If we use the criterion that color is something of the material, if for example the apple we can see red, but if we use the criterion or the old way of thinking that color is something that emanates from the apple, in this If the apple is of all colors less red since it is the only one that is not proper to it (it is not absorbed). We can say that the apple is of all colors, but not the red.
But understanding how this phenomenon happens in nature, we can already say that the colors of objects is actually the reflection of light on them or the color of light that is not absorbed ..
Bibliographical sources
http://www.fotonostra.com/fotografia/absorcion.htm
http://intercentres.edu.gva.es/iesleonardodavinci/Fisica/Luz/luz-colores/Colores.htm
