The Phenomenon of the Doppler Effect.

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Since it began the conquest on the knowledge on the space under the approach, what happens with the sun and his radioactivity, together with the discoveries relative to the atomic nucleus, they introduced a new source of energy, much major that any other acquaintance earlier, there introduced a new way of thinking on having suggested that the temperature and the pressure in the center of the sun must be extraordinarily high. The universe and the cosmos in his entire set, is like an infinite sea that keeps many mysteries for uncovering, and the big contributions that give us the phenomena that happen in spaces as the spectrums, like big contribution to the science astronomy and to the physicist, which they serve as tool to apply them in our life and to expand more the knowledge on this conquest of the spaces and the cosmos.


tTo knowing more on the phenomena that happen in the sun such as, the speed of radiation of energy for the sun implies the disappearance of certain solar mass at a speed of 4,2 million tons per second. At first sight, this looks like a formidable loss; but the entire mass of the sun is 2.200.000.000.000.000.000.000.000.000 tons, in such a way that our star loses, per second, only 0,00000000000000000002 % of his mass.


Take the “ Effect Doppler ” as a phenomenon that the astronomers had studied during a lot of time, the spectrums of the stars and were very familiar with the normal image, sequence of brilliant lines on a dark fund or of black lines on a brilliant fund, which was revealing the emission or the absorption of light for the atoms to certain lengths of waves or colors. They managed to calculate the speed of the stars that were approaching or were moving away from us that is to say, the radial speed, on having determined the displacement of the spectral usual lines towards the violet or red end of the spectrum.



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Source of image of domain of Wikimedia Commons Author: Georg Wiora (Dr. Schorsch9)Landslide to the red one of the spectral lines in the optical spectrum of a superheap of distant galaxies (right hand), compared with that of the Sun (lefthander)


To knowing more on the phenomena that happen in the sun such as, the speed of radiation of energy for the sun implies the disappearance of certain solar mass at a speed of 4,2 million tons per second. Theory of the relativity of Einstein, the absolute movement cannot be detected to the first vLa and all the observers measure the same speed C for the light independent from his movement with regard to the focus. This way, the equation 15.35, it us is valid for the displacement Doppler applied to the light, on having calculated the effect Doppler relativista we must introduce two modifications, first of all, the speed of the waves that cross with a recipient is always C, independently of the state of movement of the recipient, secondly, the interval of time between the successive emission of two waves, that it is Tf=l / ʃ r in the system of reference of the source, it is different in the system of reference of the recipient when these are in relative movement due to the dilation relativista of the time and the contraction relativista of the length.
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The signs are chosen so that they give us a displacement towards a major frequency when the focus and the recipient come closer, and the low signs are used in the análogamente, when:
u<<c, ʃ/ʃ0≈1±u/c.


Textual appointment. Physics for the science and the technology, Volume 1 for Paul Allen Tipler, Gene Mosca: pág.: 455.


Also we have the contribution of the French physicist Armand-Hippolyte-Louis Fizeau it was him who, in 1848, pointed out that the effect Doppler in the light could be observed better noting down the position of the spectral lines. For this reason, the effect Doppler is named a “ effect Doppler-Fizeau ” when it is applied to the light. It has been used by different purposes. In our Solar system it has been used to demonstrate of a new form the rotation of the Sun.


slightly much onlooker as phenomenon is the movement of the spots of the sun he allows to detect and to measure the most suitable solar rotation of form in where the above mentioned rotation, which has an approximate period of 25 days in relation to the stars). This effect can be used also to determine the rotation of objects without showy, such characters as the rings of Saturn, this theory also based by the physical investigator Armand-Hippolyte-Louis Fizeau.


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Figura 1. The displacement Doppler, the speed of the waves that cross with a recipient and the dilation relativista of the time. (IMAGE PREPARED FOR @coolxxx.)


When there is relative movement between a source with harmonic dependency with the time and a recipient, the frequency of the wave detected by the recipient tends to be different from the one that the source expresses. This phenomenon knows effect Doppler.

The effect Doppler demonstrates in acoustics and in the electromagnetism. It is probable that you have experienced the changes in frequency of the whistle of a locomotive that moves at big speed.


Textual appointment Essentials of electromagnetism for engineering for David K. Cheng pág.:279.


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Figura 2.Considering T of a wave with harmonic dependency with the time of frequency ʃ it moves with speed in or in direction that they form wave, in where the field E and H of a flat uniform wave in t = 0. (IMAGE PREPARED FOR @coolxxx.)


To know more technically at scientific level we must know the following thing, there is named a visible spectrum or light spectrum to the set of photons divided by diffraction in diverse stripes of colors from the violet the red one (in visible light) that is observed from the white light when the same one crosses an optical prism.
Represented at level of the physics with the following equation:


∆ʃ = (2∆ⱴ/c) ʃ0


The studies of these phenomena so called spectrums, it is luminous waves were begun to observe with a speed proportionally at the speed as length of this wave defined with regard with the observer, with the time waves were verified of this one also they had relation with sonorous waves, which had effect on magnetic fields creating magnetic waves. Also be observed that the difference of luminosity between two covers with stars where the spectrum the streaks corresponding to both stars appear, therefore when that of one of the components they turn aside towards the red one, another light is violet, another example on this one phenomena we have that they exist in the constellation of Perseo a star, it expresses electromagnetic field luminous.


where it was represented by the following equation, the speed of the recipient with regard to the source, it is positive when the recipient and the source are approaching.


∆f = f – f0

∆v = vr – vs

Where could be said that the speed of the wave remains constant, whereas changes take place in the wavelength; and therefore, the frequency changes also. That's why the stars are not homogeneous, due to the speed of radial between the one that they are located closer to the ground they are 308km/s, already identified like LHS52, with a distance 81.7 light years, also we have the LHS 64, with 78.2 light years, the important thing that owes to know that when it is positive he wants to say the speeds, they are removed from the sun and if the opposite was negative.


The majority that one asks himself of this about phenomena of spectrums because it has this singularity of demonstrating, the physical explanation in way of absorption is that the atoms can express not only light but also they can absorb it, in such a way that they can spend a white light to turn a gas fried it was dispersed for a prism, when this gas lowers his level of temperature, it lowers the pressure on the light, a few of the most fundamental properties of these spectrums of line of absorption the fact is that his lines appear in the same place as the lines of emission, making possible that the above mentioned gas absorbs radiations.


Contribution of the effect Doppler to the science and our life of knowledge.

It is very fascinating as the cosmos and the universe, by means of the observation, compilation of information and application of the sciences based many theories, thanks to the dedication of scientific much across the history, more to there of the Astronomy, this effect is applied in other disciplines, since it is the case of the medicine they use the Way doppler it continued (CW) and the Touched Way (PW), in his forms of spectral doppler, color and Power Angio; in such a way that it is used to evaluate the blood flow by means of the measurement of the movement of the red globules, allowing to obtain information with regard to the vascular permeability, the sense of the flow, presence of estenosis, vascular resistance distal and vascularización of the injuries.


In field of the physics also it applies it in the study of acoustics, on the other hand of wave frequency it is presented by a sound source with regard to his observer when the same source is in movement.


In the mathematical field the spectrum can be connoted in the sets of values of λ for which the operator (To - λ Î) -1 without inverse continues.


Consulted Bibliography.



Alec Eden (1992). Springer-Verlag, ed. The search for Christian Doppler. Vienna


Nicolas Witkowski, ' A train for Christian Doppler ', in ' A sentimental history of the sciences ', págs. 191-195, Century Veintiuno Editores, Buenos Aires, (2001).


Rosen, Joe; Gothard, Lisa Quinn, (2009).


Evans, D. H.; McDicken, W. N. (2000). Doppler Ultrasound (2nd edition). New York: John Wiley and Sons.



Encyclopedia of Physical Science for Joe Rosen, Lisa Quinn Gothard Facts On File, Incorporated, 2009 - 767 pages


Physics - Page 711 Raymond A. Serway, Jerry S. Faughn - (2001).


Essentials of electromagnetism for engineering - Page 279 David K. Cheng - (1998).


Physics: beginning with applications - Page 341 - (2006).


Physics for the science and the technology - Volumen1 - Page 455 Paul Allen Tipler, Gene Mosca - (2005).

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