Rainbow

The rainbow is one of the nicest natural phenomena. During years it was associated with misfortunes or catastrophes, due to the fact that any change in the weather was perceiving with the influence of the gods, as if they were signs sent by them.

Rainbow. San Juan de la Rambla. Photography realized by Yaiza Quintero González.

This phenomenon has a physical explanation, but first it is necessary to understand the concept of rainbow from the scientific point.

This one is a spectrum of light in which the “seven colors " are decomposed and observed at a glance.

If someone asks us; how many colors are really in the rainbow? We will answer that about seven, those that we see and we can count. But it is not a right answer, you have read it well, the rainbow is not composed by seven colors, the same one has thousands of them.

Isaac Newton was the first one that explained the separation of colors in the white light with the experiment of a prism (already it was spoken about it in another paragraph). After realizing the above mentioned experiment, it was determined that the light was composed by seven colors, to continue with the rule of the seven.

Rule of the seven, what does it mean? In the ancient time it was thought that the seven was a number with a strong superstition and mysticism. To understand it better, seven was the number of the perfection since seven planets existed; seven musical notes; seven days of the week; seven properties of the minerals were known... 

What is the fisiefecto of the rainbow? When the light beam enters the surface of the rain drop, the light refracts, that is to say, the colors that compose the white light suffer a separation, being able to be visible. On having gone out of these, of the drops, they suffer a new refraction that increases moreover the separation between colors.

A necessary condition, apart from the water vapor in the air, is that the Sun will be to our back, in order that these beams form angles of 138 º to form an arch.

Refraction and Reflection of a bundle of light in a water drop.

The question can always arise; why we do not see the complete arch? Because the soil prevents that we observe the other half of this arch. In some occasion it is possible to observe it, for example in the edges of a waterfall.

Finally to emphasize, every rainbow is unique, due to the position in which someone is placed to observe it.  We can see it in different shapes and colors. So, none of us won´t see the same rainbow, and on having seen every rainbow, you can feel satisfied,  you never will see the same one in the whole life, nobody except you will be able to see this rainbow.

The nature shows us many curious and nice phenomena, they can be understood and explained through The Physics.

Bibliography:

http://goo.gl/znhyL8

http://goo.gl/OVLnPy

Evolución Estelar

En las noches de cielo despejado, podemos contemplar las estrellas que llenan nuestro cielo de forma aleatoria, agrupándose en las constelaciones que conocemos hoy en día, como por ejemplo Sagitario, La Cruz, etc... Fascinados por ese espectáculo para nuestros ojos, somos conscientes que lo que observamos es el brillo de estrellas que se encuentra a años luz de nosotros y posiblemente esas estrellas no existan hoy en día. De ahí que se nos planteen dudas sobre el origen de las estrellas, del ¿cómo se forman?, ¿Cuánto  dura la vida de las estrellas? Y con ello, ¿Qué ocurre al desaparecer?

Sabemos que las estrellas también se desplazan  a grandes velocidades como cualquier cuerpo celeste, pero para nosotros ese movimiento es imperceptible, ya que están tan distantes de nosotros que resultaría la observación y estudio de muchísimo años el poder contemplar ese hecho. Si movemos un dedo delante de nuestros ojos y lo comparamos con el movimiento de un avión a gran altitud, se observa que el movimiento del dedo es perceptible en comparación con el avión que costaría percibir su movimiento.

Las estrellas nacen de la acumulación de grandes cantidades de materia, que mediante el proceso físico de compresión  y su posterior calentamiento, comienzan a desencadenar reacciones nucleares en su interior. Principalmente se componen de elementos químicos como el Hidrógeno, el Helio, Hierro, etc.., pero los más abundantes son el Hidrógeno y el Helio que son importantes en la etapa de Secuencia Principal. El brillo que se observa desde la Tierra, es la energía desprendida de estos procesos nucleares.

Gracias al avance de la Astrofísica, hoy en día, conocemos más sobre la vida de las estrellas, es decir, el ciclo de vida que tienen desde que nacen hasta que mueren. Los avances se centran en el estudio de la luminosidad- temperatura de las estrellas mediante el diagrama de Hertsprung – Russel. 

Se representa en el lateral izquierdo la luminosidad (Brillo) y en la parte superior la temperatura efectiva de la superficie (Color)

Etapas de la evolución estelar.

1. La pre secuencia principal (PSP):

La continua lucha entre la gravedad, que tiende a contraer la estrella joven, y la presión producida por el calor generado en las reacciones termonucleares de su interior,  determinan la primera etapa y finaliza con la estabilización de esta.

2. Secuencia Principal (SP):

Esta etapa es la más larga de una estrella, la cual mediante el proceso de fusión nuclear se produce la quema de hidrogeno que se encuentra en la envoltura de las estrellas, disminuyendo sus niveles de Hidrogeno (H) y aumentando los de Helio (He).

Las estrellas aumentan su luminosidad de manera regular y paulatina debido a que reducen su tamaño con su progresivo aumento de temperatura para evitar el colapso gravitatorio.

3. La etapa final de las estrellas.

Al desaparecer el Hidrogeno como fuente de combustible de la estrella, comienza la decadencia de la misma en diversas reacciones nucleares en función de su masa, podemos encontrar las rutas en las que puede desencadenar una estrella:

·         Estrellas de masa baja e intermedia ( Masa * < 9 Masa del Sol )

-          Subgigante.

-          Gigante Roja.

·         Estrellas de masa elevada ( 9 Masa del Sol < Masa * < 30 Masa del Sol )

-          Supergigante Azul.

-          Supergigante Amarilla.

-          Supergigante Roja.

·         Estrellas de masa muy elevada ( Masa * > 30 Masa del Sol )

-          Agujero Negro.

-          Estrellas de neutrones.

Para concluir , la existencia de una estrella depende del equilibrio entre los procesos de fusión encargados de producir energía en su interior, y los encargados de su transporte a la superficie. Cuando el equilibrio sufre una alteración, las estrellas experimentan variaciones (estrellas variables); cuando, en cambio, se altera completamente, puede producirse uno de los más grandiosos fenómenos cósmicos: la explosión de una estrella. Este fenómeno expande la composición de la estrella por el universo formando estrellas o planetas.

Bibliografía:

http://horizontesuceso.blogspot.com/2012/10/el-diagrama-h-r.html

http://www.cienciafacil.com/paginaestrellas.html

https://www.monografias.com/trabajos/evoestelar/evoestelar.shtml

Hurricanes

The meteorology is an important complement of Physics that tries to explain and predict the atmospheric phenomena. In spite of knowing the behavior and the origin of the phenomena, it is impossible to have a prediction reliability beyond 24 hours.

One of the most mentioned  phenomena in the last years are the hurricanes, due to the fact that are more virulent, stimulated by the climate change.

But, how do hurricanes form?

They started as storms (low pressure zones that acting with hot water oceans, increase the temperature of the surface of the water). It begins the evaporation (elevation of the warm air), whereas the surface of the ocean lowers the pressure.  The evaporated water, on having entered in touch with the cold air mass, forms the clouds (Cumunolimbus). The column of low pressure forms winds in a spiral, until it is weakening and forms a zone of scanty winds, being named an eye of the hurricane. In the surroundings of this one, the winds are accelerated.

Finally, the duration of this phenomenon is uncertain, it depends on two important factors: hot waters (> 26ºC) and high humidity.

But, how to identify the different types of hurricanes, as well as the effects?

From the beginning as disturbance, up to the evolution as a hurricane, it has different stages. The last of them is when the winds overcome 119 Km/h

How can we classify the hurricanes?

It has been classified into five categories according to the wounds speed by the Saffir Simpson's scale.

Information with the hurricanes´ types:

Category I	Category II	Category III	Category IV	Category V
119 - 153 Km/h	154 – 177 Km/h	178– 209 Km/h	210 – 249 Km/h	Superior to250  Km/h

Once the category is known, the hurricanes and tropical storms are baptized with the saints' names in alphabetical order. For the last 50 years, it was alternated the feminine and masculine one to identify, record and study it.

The effects are demonstrated by high winds, torrential rains and the increase of water levels. These provoke devastating effects in the coastline zones, due to the fact that the cyclones arrive with all the acquired strength at the ocean.

At present it has been observed that the number of hurricanes with four or a superior category are much frequent due to the climate change (the ocean temperature has increased in some tenths, being sufficient to alter the meteorological cycle).

Already we know how affects the temperature in the formation of the hurricanes, being difficult to predict it, and impossible to motorize beyond twenty-four hours.

Bibliography:

https://bit.ly/2QJb842

Coronal Mass Ejections

Coronal Mass Ejections is a term that could sound us slightly strange, but if we listen or read the word solar blazes, there comes to the mind the image of a Solar explosion. Thanks to the mass media, this term has received an importance place at present, especially in the year 2012, when a maximum in the solar cycle was waited, provoking one of these ejections that would come to our planet.

Although for some of you these articles are similar to science fiction,  we must know why they are produced and the consequences from our planet and our life too.

On September 1^st of middle of the 19th century, was possible to observe a snap of white light from the Earth that was associated with a solar explosion. For that reason, it was one of the first events that motivated this study. However we had to wait until the 20^th Century to study the solar crown as we know it today, thanks to help of the satellites. It is important to emphasize that the study must be done during the eclipses. 

The explosions happen in the mass external cap of the Sun, exactly in the solar crown, and they are one of the most energetic effects in the space. These contain Sun´s matter, principally plasma (composed by some of the periodic table elements like the Hydrogen or Helium, which are expelled to great speed. To have an idea of the speed , we can cross the distance between Tenerife and Russia during the interval of three seconds and three minutes (2000 Km/s and 50 Km/s))

These explosions have a shape of waves  and hit against the magnetosphere; to understand it better, on having thrown a stone in the water, we can observed small waves that it produces, so this it is the same idea,  but on a large scale. 

Some studies are associating the blazes with the variation of the solar spots (dark zones of the same one) during the solar cycle, which duration is 11 years approximately.

Image caught by the satellite SOHO by means of the instrumentation LASCO (Large Angle and Spectrometric Coronograph) .The opaque circle corresponds(fits) to the coronógrafo and the white circunference corresponds(fits) to the surface of the Sun.

On having hit with our exterior atmosphere, the energetic particles, which contain the solar eruptions, provoke a visual effect in the terrestrial atmosphere: these are the northern lights. This phenomenon indicates that our atmosphere is being bombarded by energetic particles of the interstellar way. Though not always they remain in a simple visual effect, but it can cause a major consequence.

Aurora borealis.

We must not be ignoramuses with our environment, and for that reason there are big investigations groups that are centering on the detection and prediction of this phenomenon, which has always happened. Because it can cause not only electrical blackouts (in the local network, as on a worldwide scale), but also erroneous reading in GPS, fall of internet, etc.... This is due to a network saturation, which complete reestablishment might last from months to years.

 The main question is: Will we be able to avoid the serious consequences in case of suffering a geomagnetic storm?. A rapid detection facilitates us the power of extinguishing the electricity generating equipments and to avoid the overload, due to the fact that the plasma contains neutrons and electrons. These two last are the managers of generating electricity and to overload the electrical network, provoking the burning of generators and other consequences.

The storms have always existed and they will exist, owning that fact that it is natural process and we have a magnetic field that protects us. It is of emphasizing the blackout of March 13^th , 1989 in Quebec (Canada), which city remained without electrical net for 24 hours because it was fused several generators that supplied the city.

Nowadays these effects are more notable thanks to the technological advance, due to the fact that we can feel the effects of the storms; because we were not as dependent on technology as we are now.

Bibliography:

http://bit.ly/1gRUEmL

http://bit.ly/1iyQfX0

http://bit.ly/1QB6M7O

Presentation

Hello to all,

I would like to greet all the possible readers of this Blog of Physics (The mother of all the sciences jajajaj). I hope that the word does not throw (add) for behind anybody at the moment of reading the articles that in I will be publishing, already be for fear of not dealing, or for boredom.

With this Blog what I want is to spread the Physics of a simple way and come with everything the public ones, that could understand otherwise, not the typical one that they teach (show) during the student life, that enclosed we can manage to hate these subjects of science (Well because we do not like them; because the one who gives it stops much thought to wish; because it is indefensible …)

The Physics is something that surrounds us since we are born until we die, that even even after our death, guess that.... There is physics, In all the moments of our life we are surrounded by her(it), but we ignore her, we do not know the importance that has not even the effect that produces in our lives. It is because of it that I want to spread so that in day after day demos importance to what it(he,she) surrounds us with certain interest ( As physicist it is my aim(lens) and I wait to fulfill it).

And, why Fisiefecto?. The Physics can be summarized in effects, everything what includes the Physics they are effected. For example and the more known by all, the rainbow. In there is a visual effect but that has an explanation and physical checking that already I will revel in someone of my articles. So better that to say reason and effect; we say Physics and effect.

Regards,

From Fisiefecto.

Huracanes

HURACANES

La meteorología es un campo de la Física encargado de explicar y predecir los fenómenos atmosféricos. A pesar de conocer su comportamiento y el origen de ellos, a día de hoy, no es posible tener una fiabilidad de predicciones más allá de las 24 horas.

Uno de los fenómenos más mencionados en los últimos años son los huracanes, debido a que cada vez son más virulentos, incentivados por el cambio climático.

Pero, ¿Cómo se forman los huracanes?

Empiezan como zonas de baja presión (tormentas) que actuando con océanos de agua cálida, aumentan la temperatura de la superficie del agua. Se inicia así, la evaporación (elevación del aire caliente), mientras que la superficie del océano baja su presión.  El agua evaporada al entrar en contacto con la masa de aire frío, forman las nubes (Cumulonimbos). La columna de baja presión forma vientos en espiral, hasta que se va debilitando y forma una zona de vientos escasos, denominándose ojo del huracán. En los alrededores de este, los vientos se aceleran. 

Estructura interior de la formación de un Huracán

Finalmente, La duración de este fenómeno es incierta, ya que depende de dos factores muy importantes: aguas cálidas (>26ºC) y alta humedad.

Pero, ¿cómo identificar los diferentes tipos de huracanes, así como sus efectos?

Desde el inicio como perturbación, hasta su evolución como huracán, pasa por diferentes etapas. Esta última la alcanza cuando los vientos superan los 119 Km/h.

¿Cómo podemos clasificar los huracanes?

Gracias a la escala de Saffir Simpson, estos se clasifican en cinco categorías según la velocidad de sus vientos. A continuación una tabla de información con los tipos de huracanes:

Categoría I	Categoría II	Categoría III	Categoría IV	Categoría V
119 - 153 Km/h	154 – 177 Km/h	178– 209 Km/h	210 – 249 Km/h	Superiores a 250  Km/h

Una vez se conoce su categoría, los huracanes y tormentas tropicales son bautizados con nombres de santos y por orden alfabéticos. Desde hace 50 años, se han empleado de forma alterna los nombres femeninos y masculinos para identificarlos, para su posterior registro y estudio.

Efectos del huracan Katrina 2005 (https://bit.ly/2D6Z9u3)

Los efectos que provocan estos fenómenos violentos, suelen manifestarse por medio de vientos muy elevados, lluvias torrenciales y crecidas del nivel del mar. Estos provocan efectos devastadores por los lugares que lo atraviesan, debido a que suelen ser zonas costeras, donde los ciclones llegan con toda la fuerza adquirida durante su trayecto por el océano.

En la actualidad hemos observado que el número de huracanes de categoría cuatro y superior son demasiados frecuentes, este hecho debe plantearnos que el cambio climático está ocurriendo a pasos muy acelerados. Ya que el agua de los océanos ha aumentado su temperatura en algunas décimas, siendo suficiente para alterar el ciclo meteorológico. 

Ya sabemos cómo afecta la temperatura en la formación de uno de los efectos meteorológico más virulentas existentes, difíciles de predecir su trayectoria, e imposible de motorizar más allá de veinticuatro horas.

Bibliografía:

https://bit.ly/2QJb842

https://bit.ly/2PLXZG9

https://bit.ly/1poHaDy

https://bit.ly/2NnNtry

https://bit.ly/2D6Z9u3