Hola a todos:
Debido a problemas que hemos tenido con las plantillas del sitio (Hace ya tiempo que perdimos el formato del blog y no hay manera de recuperarlo o de cambiarlo por otro), nos hemos trasladado a
http://fisilucas.wordpress.com
Perdón pòr las molestias
As a project of the second term, we have manufactured a submarine:
In this project we had to make a model of a submarine that could more or less do what would do a real one.
Our submarine began as an almost impossible project, but despite the adversities we managed to take it forward and make our submarine afloat, dive and return to the surface.
· Materials:
We used a few materials to do our submarine:
One PVC pipe
A little bit of plaster
Two balloons
One small pipeline
Four syringes
A tape
Some red, black and yellow sprays
· Development:
First we started working with a submarine, but had to leave because the submarine was heavy and did not rise to the surface, then had to change and start working with a submarine ascended to the surface, we put a grout and a syringes to submerge or float the submarine
· Characteristics:
The submarine is 50cm long and 9cm in diameter but the main idea was to do it in 1m long and 12cm in diameter. The material we used is PVC. The color of the submarine is mainly black but with red spots, so we wanted to ‘mess it’ to make it look more real.
· Ending:
In this project we have learned how to work together and coordinate. We thought we could not do a submarine that could float, dive and we have achieved with great dedication this project.
Ángel Palazón, Adam Garcia, Victor y Jose María Peregrín y Mario Landáburu
In this article about our school project, “building a submarine”, we had several difficulties in getting our submarine to do the three main targets in the project:
Make it be able to dive and come back up to the surface.
Get the submarine to be stable.
Make sure we have a waterproof compartment where we would inhabit.
First we had to find what would be the body of our submarine. We thought about using bottles, cans and several other objects, but we decided to use water pipes. After getting these from a plumbing shop we took it home and made a hole on the side of the main tube. Then we had a brainstorm where we would decide how it would accomplish our goal number two. The technique that we agreed to use was a manual pump connected to two balloons regulated by two taps meaning we have total control over the vertical movement of the vehicle. When we finally got it working we started with our target number one. With this task at hand, we tried making the underwater vehicle have a great stability, we put a base of cement in the bottom, getting the right weight for it to be able to come back up and not only sink.
We had to calculate the volume, the weight needed for the sinking of the submarine and also the buoyant force we had to exercise in order for it to float.
We added an air compartment that had a small playmobil girl, very pretty by the way. We waterproofed it so no water could get in, we put the girl inside on top of a silicon bag so any condensation was absorbed, and once we had done that we closed it and sealed it with hot silicon. Once this was dry we placed it in the whole that was already made.
Also, although it wasn’t obligatory, we dared to put a motor in. We recycle some motors that we have of little toy cars. Finally, we put these 2 in the below laterals.
We don’t have to paint it, but we decided we wanted to. We thought that it would be more original and would be a way to show our personal design. So we painted it silver-colored, because that was the only color we had in our houses and in this way we didn’t have to spend any money, also it gave it a bit of a alien like look.
After doing all of this and thinking it was done we had a problem, the stability was not in the middle, so it went to one side. We decided to get rid of the cement and put two tubes with metal weight either side to make it stable.
We finally had our submarine.
Project made by:
Mª José Hernández Sáez
Talia Corroto García
Nerea Salas Pérez
Here we have the new submarine with the highest quality in the market. Sub-77, alias: Xiphactinus, is a submarine with a minimalist and innovative design, with a look of aggressive nature in all its facets.
Submarine Construction The submarine, like any other , float and dives stably by an air injection system thanks to an air pump, through a system of tubes with closures. After placing its corresponding ballast iron, stability problems have been solved by injecting polyurethan in two-thirds of the internal part,located in fore and aft.
The main material used is PVC (camera and external tube) .Also iron has been used for ballast and polyurethane for the internal cave. You can see a photograph of the internal part without the poliurethan and a photo of our great product!
Enjoy it!
Todo profesor de física se encuentra con este "problema" cuando, llegadas estas alturas del curso, tiene que explicar la óptica geométrica: ¿Qué criterio de signos utilizo?
En realidad no es un problema, porque cada persona lo tiene claro desde un principio, tiene su sistema favorito y es el que utiliza un año tras otro. Sin embargo , ¿qué es esto del criterio de signos?
Es algo que hemos estado usando desde hace bastante tiempo. Desde el momento en que en matemáticas aprendimos a utilizar los números negativos, estamos usando implícitamente un criterio de signos. Normalmente las distancias, velocidades y, en general, cualquier magnitud que vaya a la derecha la consideramos positiva y cualquier magnitud que vaya a la izquierda es negativa.
Si tratamos un problema vertical, hacia arriba se considera positivo y hacia abajo negativo.
Así pues, si tenemos un objeto a la izquierda de una lente, lógicamente su posición será negativa, y si está a la derecha, su posición será positiva. Tal y como hemos estado haciendo siempre.
¿Por qué cambiar este sistema de referencia?
Bueno, para los teóricos de la óptica, los que hacemos ejercicios sobre papel, nos resulta muy cómodo seguir usando este criterio. Incluso cuando hacemos montajes prácticos, lo aplicamos sin problemas. Sin embargo, para los ópticos que están todo el día frente a lentes y espejos reales, les resulta más fácil distinguir entre espacio objeto y espacio imagen.
El espacio objeto de una lente es el que está delante de ella, y aquí, las distancias para los objetos son positivas y para las imágenes son negativas. De esta manera se ahorran arrastrar el signo menos cuando se coloca el objeto delante de la lente, que es en la mayor parte de los casos.
De forma análoga, en el espacio imagen (tras la lente) son las imágenes las que se miden con el signo positivo.
Este pequeño cambio de criterio, que se hace por comodidad y para evitar errores debidos al signo, modifica ligeramente las distintas ecuaciones que usamos durante el curso.
Para que quede claro, y puesto que nosotros vamos a utilizar el criterio de signos matemáticos usual (a la izquierda con signo menos), vamos a plasmar aquí las ecuaciones que se usan a lo largo de este tema:
Hemos de tener en cuenta que las magnitudes sin ’ se refieren al objeto, y las magnitudes con ’ se refieren a la imagen, así la distancia objeto es s y la distancia imagen es s’.
Asímismo, es interesante notar que si tenemos una superficie cóncava el centro de curvatura estará a la izquierda del vértice y por tanto nos saldrán radios negativos. En el caso de las superficies convexas saldrán radios positivos.
Dióptrio esférico:
n2/s’ - n1/s = (n2-n1)/R
Ya sabemos que si hacemos que el radio sea infinito, tenemos un dióptrio plano:
Dióptrio plano:
n2/s’ - n1/s = 0
En los dióptrios el aumento lateral, o relación entre el tamaño de la imagen y el objeto se determina de la siguiente manera:
β = y’/y = n1 s’ / n2 s
Asímismo, podemos obtener las ecuaciones de los espejos considerando el índice de refracción n2 = -n1 en la ecuación del dióptrio esférico:
Espejo esférico:
1/s’+1/s = 2/R
ó, considerando que la focal siempre es la mitad del radio de curvatura:
1/s’+1/s = 1/f
Espejo plano (R--> ∞)
1/s’+1/s =0
En los espejos , el aumento lateral es:
β=-s’/s
Por último en las lentes delgadas, en las que suponemos una lente formada por dos dióptrios muy próximos entre sí, tanto que se confunden el vértice de los mismos, tenemos la
Ecuación del constructor de lentes:
1/s’- 1/s = (n-1)(1/R1 - 1/R2)
Que, si tenemos en cuenta las distancias focales, en vez de las características físicas de la lente, se puede transformar en:
Ecuación de Gauss de las lentes delgadas:
1/s’ - 1/s = 1/f’
El término 1/f’ se denomina potencia de la lente y se mide en diptrías (si la focal f’ se ha medido en metros)
En las lentes, el aumento lateral es:
β= s’/s
Aprovechamos que esta semana se celebra el día del libro para recordar un tema ya tratado en un artículo en 2007:
Lo recordamos porque el próximo sábado (23 de abril de 2016) hará 400 años del fallecimiento de Miguel de Cervantes Saavedra y de William Shakespeare. Una fecha insigne y una efemérides que será recordada una y otra vez en los medios de comunicación a lo largo de estos días.
Sin embargo, a poco que busquemos, podemos comprobar lo siguiente:
¿Nos mienten, por tanto, los medios de comunicación?
¿No murió Shakespeare el 23 de abril?
La respuesta a la segunda pregunta es afirmativa. El escritor inglés murió el 23 de abril de 1616, según el calendario que imperaba en aquellas fechas en Inglaterra, que era el calendario juliano, mientras que en España ya teníamos desde hace algunas décadas el calendario gregoriano (el que usamos actualmente).
Así pues, este viernes sí harán 4oo años de la muerte de Cervantes, pero para conmemorar la de Shakespeare habrá que esperar todavía 2 semanas.
En el marco de la asignatura de ampliación de física y química de 4º de la ESO, hemos desarrollado un proyecto a lo largo de este corto 2º trimestre.
Teniendo en cuenta la experiencia marinera del centro (el año pasado se construyeros barcos que debían flotar (!!) y ser navegables), este curso hemos querido dar un paso más y aprovechar lo que hemos aprendido en el tema de fuerzas en fluidos (principio de Arquímedes, condiciones de flotabilidad,...) y construir submarinos que cumplan las siguientes condiciones:
Lo cierto es que los alumnos se han esforzado mucho y han solucionado los problemas surgidos con ingenio y aportando soluciones distintas.
Proximamente vamos a publicar unos artículos, realizados por cada grupo, en el que vamos a ver los problemas que han tenido y las soluciones que les han dado.
En fin, aunque ya nos hemos despedido en persona en el instituto, o quería pasar la ocasión de desearos a todos un feliz verano.
Disfrutad y descansad, que vais a necesitar muchas fuerzas el curso que viene.
Hoy en día hay que combinar los métodos tradicionales con los propios de los tiempos en que vivimos en la enseñanza de la física y la química
3º ESO. Tema 1.
Tal y como comento en clases, el primer tema de la asignatura es un cajón de sastre en donde se dan herramientas que vamos a usar a lo largo de todo el curso, y donde, a veces, cuesta trabajo ver la relación que hay entre la notación científica y la precisión de una medida, por poner un ejemplo.Dentro de todo este batiburrillo estudiamos el método científico, y su importancia puede pasar desapercibida, ya que nos da la impresión de que "es teoría para el primer examen" y no vuelve a salir en todo el curso.
Falso. Usamos, o deberíamos usar, el método científico una y otra vez, no sólo en una asignatura de ciencias como ésta, sino en nuestra vida cotidiana. El método científico es una manera de ver las cosas, de ordenar los pensamientos y de clarificar las ideas antes de realizar una acción. En realidad tan sólo es ordenar los pasos que se han de seguir a la hora de resolver un problema.
Dice la teoría que los pasos (más o menos) son estos:
Parece bastante sencillo y tonto. Sin embargo, el seguir estos pasos ha permitido al mundo avanzar enormemente en los últimos 3 siglos. El primero en hablar de ellos fue Descartes -filósofo del siglo XVII - en su obra "El discurso de método" en 1637. Hay que recordar que en aquella época los filósofos incluían el estudio de la naturaleza, lo que incluían las matemáticas y lo que hoy es la física y otras ciencias.
Antes de Descartes ya se habían seguido estos pasos, pero con lagunas. Obviamente, los pasos 1 y 2 se dan desde que el hombre es hombre y siente curiosidad. Los pasos 3 y 4 también se realizan desde el principio de los tiempos, ya que hemos ido avanzando a base de la técnica de ensayo y error, y hemos ido compartiendo lo descubierto con los nuestros para preservarlo y vivir mejor.
La verdadera fuerza del método científico, está en realizar todos los pasos. Alguien tan insigne como Aristóteles (384-322 a.c.), filósofo y filósofo natural que abarcó enormes áreas de pensamiento y estudio, seguía tres de estos cuatro pasos (desde luego que publicó los resultados, de hecho ha sido una de las personas más influyente en Europa durante casi dos milenios gracias a ellos). Sin embargo, Aristóteles no experimentaba. No porque no se le ocurriese hacerlo, sino porque dentro de la mentalidad griega de la época se pensaba que si una lógica aplastante te llevaba a una conclusión, el tratar de demostrarla mundanamente era innecesario. El mundo puro de las ideas era superior al mundo físico y siempre tendría preponderancia.
Así, cometió algunos errores de bulto, como apoyar la concepción geocéntrica del universo (aunque en aquella época no había medios para comprobarlo) o pensar que los cuerpo caían más rápidos cuanto más masa tuviesen. Un simple experimento como el que realizó Galileo en la torre de Pisa , 18 siglos después, le hubiera sacado de su error, a él y a las incontables generaciones que tomaron sus enseñanzas como dogma de fé. ¡Quién sabe donde estaríamos sin semejante retraso!
La culpa no es exclusiva de Aristóteles. Durante la edad media los alquimistas - precursores de los químicos - también se saltaban un paso en el método científico, en este caso la publicación de resultados. Consiguieron hacer notables avances en lo que hoy llamamos química, pero debido a lo cercanas que estaban la experimentación que realizaban a lo que sus contemporáneos consideraban brujería, y debido al poder que ellos creían poseer gracias a dichos conocimientos, y que no querían para nadie más, se guardaban lo descubierto, y apenas lo compartían, y de forma parcial, con sus discípulos. Obviamente, el avance científico era lento de esta manera.
La gran ventaja de la aplicación del método científico es la gran cantidad de personas que pueden acceder al conocimiento.
"Si he visto más lejos es porque estoy sentado sobre los hombros de gigantes"
Esta frase, atribuida a sir Isaac Newton, resume el paso nº 4. Incluso alguien como Newton no habría podido descifrar la fuerza de la gravedad si Robert Hooke no le hubiese enseñado a descomponer las trayectorias curvilíneas.
Cuando un científico hace un progreso y lo comunica al resto de la comunidad científica, se asegura de poner su granito de arena en el conocimiento, de dar un paso que quizás sea otro científico el que lo aproveche. Pero finalmente es la humanidad la que da todos los pasos, la que avanza en el conocimiento y la que puede conseguir una mejora en nuestras condiciones de vida. Algo que hubiese sido imposible con la labor de un sólo hombre.
El método científico auna nuestros esfuerzos y nos permite conseguir metas que a veces parecen increibles.
Corregido el último examen del trimestre, para la mejora de notas de la semana que viene habéis de prepararos las siguientes evaluaciones:
Manuel Hernández --> 2ª con peligro.
Victor Aguilar --> 1ª con peligro.
Jose Alfonso Casanova --> 3ª septiembre
Clara Castillo --> 3ª
Zakaria El Mansouri --> 3ª
Juan Galiá --> 1ª
Rocío González --> 2ª con peligro
Antonio Liarte --> 2ª
Pepe Martínez --> 3ª
Rocío Monteagudo --> 2ª
Alejandro Ortega --> 1ª
Alfonso Ragel --> 3ª septiembre
Pilar Soto --> 3ª con peligro.
DNA DOUBLE HELIX
One morning of March two young scientific, the physicist Francis Crick and the biologist James Watson announced that they have been obtained the structure of the DNA. This discovery, that revolutionized the world of the biology, was enunciated in 1953. In 1951 Watson was installed in Cambridge to share with Crick the adventure of determining the structure of the DNA. At this moment, the only available technology to visualize the structure of big molecules was the diffraction of X-rays, that consist in something similar to X-raying a molecule.
Parallel, the physicochemical Rosalind Franklin and the biophysicist Maurice Wilkins realized studies crystallographic of diffraction of X-rays on molecules of DNA. In 1952 Rosalind Franklin obtained a photography of diffraction of X-rays that it revealed the spiral structure of the molecule of DNA. Wilkins, without the consent of Rosalind, gave the photo to Watson and Crick. For them the image constitute a definitive information to determine that the structure of the DNA corresponded to a double propeller, and not triple since it was thought. Rosalind Franklin died in 1958 with 37 years old, four years after Watson, Crick and Wilkins got the prize nobel of physiology and medicine for his contributions to the discovery of the structure of the DNA. Franklin’s inestimable contribution to this discovery, was never recognized, but little by little the history starts valuing his labor.
First we are going to explain some important things to understand the DNA in general and why it is important for us:
1. The human genome or genetic map is the total number of chromosomes of the body.
2. The chromosomes contain approximately 80.000 genes, responsibles of heritances
3. A gene is the physical, functional and fundamental unit of the inheritance. The importance of knowing the genome is that all the diseases have a genetic component.
4. A gene, it is a fragment of DNA as which it has the only sequence of base couples, which can use for difference a few genes of other one and fix his position in the chromosome.
5. The information of the genes has been decoded and allows to the science to know that diseases could have a person in his life, this knowledge could treat till now incurable diseases.
6. The most important thing of the chromosome is the molecule of DNA. Molecule of double propeller, with which every propeller is antiparallel and this formed by chemical compounds so called nucleotides. Each nucleotide consists of three parts: group phosphate, desoxirribosa, and four nitrogenous bases: adenine, guanine, thymine, and cytosine .These components are connected.
7. The DNA that forms the genome contains the necessary information to construct and to support life.
8. The genome is the whole DNA of an organism, included the genes, which take the proteins needed by the organism that determine the aspect, functioning, metabolism, resistance to infections and other diseases.
9. The genetic code comes determined by the order that the nitrogenous bases occupy.
10. The genetic code makes us as we are
This dicovery of DNA double helix is very important. But we have a problem because de genetic map isn’t complete. We are going to tell you what is the human genome project and why it is very important:
It is a international programme of scientific collaboration which it objetive is have a basic knowledge of the complete human genetic dotation. This genetic information is founded in all the cells of the body encoded in the DNA.
The programme aims to identify all the genes of the core of the human cells, establish the place of the genes in the chromosome core and determined via the sequenciation.
The objective is the secuentation of the human genome and representation is associate features human specific and diseases inherited with genes located in precise location of the chromosomes. The human genome project a knowledge without previous proportionate of the organization of the essential genes and chromosomes human. Promises to revolutionize the treatment and prevention of many human diseases that penetrate the basic bioquimics phenomena that sustains.
The human genome project is an international investigation that found select to mapping you the DNA sequence. It is intended to register genes encoded the necessary information to build and sustain life.
Some objetives:
Some objetives:
-Identify approximately 100.000 human genes in the DNA
-Deterine the sequence of 3 billion os bases chemical oh the DNA
-Accumulae information of database
-To develop tools for data analysis
-The purpose is to provide the world with innovative tools for the treatment and prevention of diseases.
-The genetic map is a genetic tool that it allows study the evolution and it could change the medicine.
-It allows the treatment of diseases until now uncured.
- With the knowledge of the human genome, we know the code before we could only configure the program.
- You could tell a person of the diseases that he could have.
- This could change medicine forever giving a new power to cure especially in the diagnosis, treatment and prevention of diseases such as: alzheimer, parkinson, diabetes, cancer, heart problems, schizophrenia and all the complications that have a genetic origin.
-The Project has needed ethical, legal, social and human analysis.
But this problem has moral problems, such as genetic racism (any person is less than one for his genetic code), who can access this information and use it for other things than the cure of diseases ...
Is our planet the only planet in which life exists? We don’t think so, because there are many arguments to think that there are several kinds of life in other planets.
There are many constructions of ancient civilizations that were advanced to their period like the Egyptian and Inca people who built a lot of pyramids in their zones. We think that these constructions were built with extraterrestrial help. Archeologists found many paintings about people that were in flying machines and strange technologies, many of these paintings were discovered in Southamerica.
Ancient civilizations also sculpted and painted many different things which represented their gods, the gods that they had seen or the ones they believed in. We think that during all the history people have had extraterrestrial help and influence in their life. Many of these constructions of Egyptians, Incas or people from Mesopotamia were related with the astronomy, they were very interested in that world out of their hands and knowledge that maybe supposed a relation with something that came from the space.
Archeologists had found many documents and draws of Mesopotamia and Egyptian civilization in which appear strange humans with features of an advanced race. In this documents and draws appear strange machines or tools too, to draw these engravings. Many experts are sure that many of this constructions, tombs or figures had been made with tools with the precision of a laser.
One of the aliens’ signs is the discovery of rests of H20 in other planets. We think that it’s probably that there is water in other planets with a good climate because the universe is very big and maybe there are other planets with intelligent life.
We are sure about this affirmation because physic’s and chemical’s laws are the same in every part of the universe.
One clear sign of the existence of aliens is the sight of UFOs. There are a lot of UFO’s sightings all over the world. There are a lot of theories about why the aliens are sometimes in our world.
Some people say that they represent the peace of our civilization, other people think that the day when they definitively come to our world will be the last day: the apocalypse or doomsday.
The UFOs are flying machines that we (the humans) cannot identify. The term UFO means unidentified flying object. During the last century there were a lot of sightings of UFOs, especially from the middle of XX century.
There are a lot of people that say that they have been abducted by aliens. Some theories say that they are only studying us, that they don´t want to attack us. There is also a person that said that he was abducted by them and they told him that we are their experiment and they are only admiring their experiment. They told him that they were so advanced to create life and they originated it in the Earth. Another theory suggests that aliens are humans from the future who have found out the secrets to travel through the time, using maybe wormholes.
It’s very sure that Nazis during War World II contacted with aliens because after the war in laboratories Nazis, plans of flying discs like UFOs were found, they were planned to make this flying discs with an advantaged technology, these plans exist today and you can see them in internet.
We think that there will be the day that they will come to our planet and they explain the life’s significance or they will kill us, we aren´t sure about this… but we are sure that they are waiting for that special moment.
Here are some videos that explain our theory, they are in English with Spanish subtitles.
http://www.youtube.com/watch?v=6dj1GXFHhCc&feature=related
http://www.youtube.com/watch?v=ZZcAxhyccsA&feature=related
http://www.youtube.com/watch?v=iQJUKdALLpo&feature=related
The three formulas Stephen Hawking to travel in time
“Is it possible to travel in time?” Can we open a portal to the past or find a shortcut to the future? ". The great British physicist Stephen Hawking made these questions in an article published in Daily Mail cosmologist offered not one, but three realistic theoretical formulas to answer your question, three proposals that may make it possible for an idea has long been a scientific heresy. In their view, such a venture is not as preposterous.
To begin, Hawking suggests that it is essential to open the mind to the idea of the fourth dimension: time. The scientist uses a very simple example, that of driving. When we travel by car and drive in a straight line travel in one dimension. If we turn right or left, we add a second dimension. If you also go up or down a mountain road, we find the third. The fourth dimension is time, but how do we find a way to travel through it? :
1) Wormholes:
"The science fiction movies show a large power-hungry machine that creates a tunnel through time. A time traveller, a brave, ready for who knows what into the tunnel and emerge who knows where (...) The reality may be very different from this, but the idea itself is not so crazy, "admits Hawking in his article. For physicists, the tunnels can be time wormholes. "They are all around us, in the cracks of space and time, but are too small to see them," explains the scientist. "At the smallest scale, even smaller than molecules and atoms, quantum foam exists. This is where there are wormholes, small tunnels or shortcuts through space and time constantly form and disappear. "
Unfortunately, these tunnels are too small for a human being can look through the keyhole. They measure only a thousand million billion trillionth of a centimetre, but it may be possible to take one of them and make it large enough for human beings or even a spaceship. In this way we could travel to other planets located light years away and "maybe the dinosaurs on Earth could see a ship landing."
Of course, the wormhole is a small problem, which Hawking calls "the paradox of the mad scientist." What if a scientist uses the hole to shoot his past him? Now he’s dead, but who shot? It is a paradox, it doesn’t make sense. It’s the type of situation that causes nightmares for physicists. This kind of time machine would violate a fundamental rule that governs the entire universe: the causes of the effects happen before, and never the reverse. The trip back would be impossible, but what about the future?
2) Black holes:
"We think that time flows like a river, at different speeds in different places, and that is the key to travelling in the future," says Hawking. This idea was proposed by Albert Einstein one hundred years ago, realizing that there should be places where time runs slower and others where it is accelerating. "He was right and the proof is over our heads" in the space, says Hawking. The time goes faster in space. Within each spacecraft is a very accurate clock, but despite this, everyone wins about a third of a billion seconds each day. The problem is not with the clocks. What happens is that the mass of the Earth drags time and slows.
In the center of the Milky Way, 26,000 light years away, is the heaviest object in the galaxy: a super massive black hole slows the time more than anything else in the galaxy. "It’s like a natural time machine," says Hawking. If a spacecraft went into orbit in the hole, it would take 16 minutes to complete one orbit to the space agency that would control the mission from Earth. For the astronauts, would only last eight minutes. If you spend five years in orbit, actually have been ten. When will they come to Earth, all the others have aged five years older than them. The problem? Approaching a black hole is too dangerous.
3) Travelling at nearly the speed of light:
Third time lucky. For Hawking, the solution may travel very fast, even more than the required speed to avoid being swept away by a black hole. According to Hawking, travelling at nearly the same speed of light, 186,000 miles per second, take us into the future. To explain, the scientist imagines a super-fast train that would circle the Earth seven times per second, which does not reach the speed of light, something that the laws of physics forbid. Then time begins to run slowly on board, as if we were near a black hole, but more so, as in slow motion. In one week, the train would travel one hundred years in the future. Of course, building a train to reach those speeds is impossible, but we have built something very similar: LHC particle accelerator of the European Centre for Nuclear Research (CERN) in Geneva, Switzerland. We know particles, pi-mesons, which usually disintegrate but ipso facto, when they are accelerated to nearly the speed of light, lasting 30 times longer.
Hawking concludes that if we travel to the future, we just have to go very fast, something that is only possible in space. This would require a ship 2,000 times faster than the Apollo 10, of enormous size and that could carry a lot of fuel, enough to accelerate to nearly the speed of light. "Four years after takeoff, the spacecraft will begin to travel in time. For every hour on the ship, two would on Earth, "he explains. After two years of full speed, the spacecraft would reach its peak, 99% of the speed of light. Then, one day on board would be a year on Earth. Our ship would fly to the future.
Right now we see through the streets and highways are many types of vehicles from small city to the large displacement that most dream to have someday. Most of them powered by petroleum products such as gasoline or diesel with its effect on the environment is evident. In a short period of time the cars will suffer major changes, and some of these are the changes in performance and reduction of CO2 emissions into the atmosphere, these changes are made to change the diesel engine / petrol to hydrogen appears a good alternative that is being investigated but, right now, the technology "spike" is within the power. There are two types of cars that use this energy source: diesel-electric hybrids and pure electric.
Electric cars
The engine of these cars powered by batteries that are not nothing but containers of chemical energy and chemical energy that can be transformed to become electrical energy. The batteries, or batteries, are divided into two groups, primary and secondary schools. Primary batteries are based on an irreversible chemical reaction, ie can not be recharged and have a single use. Secondary batteries, in turn, are based on reversible chemical reactions, so it can be recharged a certain number of times. Electric cars work, therefore, secondary batteries.
The power is the cleanest to avoid contaminating anything but in the process of obtaining energy (power plants, nuclear ...). It has three fundamental problems since its speed is not very high, very little hard autonomy and the necessary infrastructure is not mounted.
Hybrid cars
Hybrids have two advantages as their autonomy and speed are higher but have a problem since, when the electric motor is over, "jumps" the diesel which is contaminated but not as much as "normal." Additionally, you can benefit from the infrastructure of service stations. It’s pretty quiet but the power is even quieter.
The problem right now is also the price as it is quite expensive but the expectation is that prices are reduced more than 25-30% and even half in just five years. Although we can see on the street some models of Honda or Lexus hybrids of 18000-24000 € but does not fall.
These are examples of cars near future also other types of cars, but only marketed in 2020, which is a bit far to explain many facts not known.
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First, we have to save energy by using public transport instead of our own cars or walking, by using low consume bulb. We have to install solar panels in our houses to begin. Then, we will use renewable energies like solar power, tidal energy, wind power and geothermal energy.We must search into nuclear fusion energy.
We think that one of the best forms to solve the energetic global problem. It consists of trying to establish an energetic diversity not to depend on a limited group of not renewable energies since they would become exhausted before. In fact, already it is, nevertheless it is not sufficient, because we still depend in 80% of the not renewable energies in the developed countries.
A Norwegian Professor, Egil Lillestol, believes that Thorium power plants could help solve the global energy crisis. Norway has a huge amount of Thorium and a Thorium reactor has lots of advantages over a traditional nuclear power plant. The world’s reserves of Thorium could cover the energy needs globally for thousands of years.
Another solution is to improve renewable energies. Solar power is a great option, we can place solar panels in a big desert or send a geostationary satellite with big solar panels that send by microwave rays to a receiver station in the earth, but one of the problems is that in deserts, sandstorm can destroy the panels.
Tidal power could be in the future an important energy; tidal power stations use wave movements to generate electricity. If we put big extensions of this central in the sea we can obtain a lot of energy. But nowadays it is not well-known; Scientifics have to study it more.
But all this energies don’t generate so much energy, so, for this problem we have to generate energy by nuclear stations, that generates a high quantity of energy and don’t contaminate with CO2. Nowadays this type of central has more security than twenty years ago, and it’s very difficult that can have a leak of toxic substances. However this kind of energy has a problem, where we put the radioactive waste?
We think if the countries work together as one it will be easier.
Como ya sabéis, en este tercer trimestre vamos a realizar un trabajo de investigación optativo(cuya temática incluiré posteriormente) Podrán realizarlo los alumnos de 4ºA y 4ºB, mezclados si queréis, porque todo el trabajo se realizará onLine através de este blog. Los grupos serán de 3 alumnos y habrá un máximo de 14 grupos. Todo esto es voluntario, naturalmente, pero lo evaluaré, y la nota contará como la de medio examen (es decir, que los que lo hagan les haré la media como si hubieran hecho 2’5 exámenes en este trimestre).
Los aspectos generales del trabajo son los siguientes:
Espero vuestra participación.
Uno de los aspectos de la física más familiares para el público en general es la meteorología. Estamos acostumbrados a recibir nuestra ración diaria del pronóstico del tiempo, a tomar decisiones sobre lo que haremos dependiendo del tiempo que vaya a hacer, y de echarles la culpa a los meteorólogos cuando se equivocan, cosa que a pesar de los avances tecnológicos sigue ocurriendo.
En estos días, el interés por la meteorología no está centrado en las lluvias ni en las temperaturas, como suele ser habitual, sino más bien en los vientos. La erupción del famoso volcán islandés (del que nadie dice el nombre: Eyjaffalla ¿por qué será?) está soltando miles de toneladas de ceniza volcánica a la estratosfera. Estas cenizas son muy peligrosas para los motores de los aviones porque al introducirse en los motores, a altas temperaturas, se cristalizan provocando daños en ellos, hasta poder hacer que fallen y el avión caiga. Por tanto, en toda la zona en la que hayan presentes cenizas en suspensión, a un nivel por encima del crítico, ha sido suspendido totalmente el vuelo de aparatos, causando el caos que vemos en las noticias.
¿Hasta cuándo durará ésto? La respuesta es un depende. Este tiempo dependerá principalmente de dos factores: del nivel de cenizas que siga echando el volcán a la atmósfera, y de la dirección en la que sople el viento.
Del primer factor que hablen los geólogos. No soy un experto, pero supongo que esto no durará dos dias.
En cuanto a la dirección del viento, sabemos que sopla dejando las bajas presiones a su izquierda en el hemisferio norte (debido a la fuerza de Coriolis), por lo que mientras la situación meteorólogica se mantenga estable en el Atlántico norte los vientos seguirán soplando en la misma dirección. Por fortuna, vivimos en unas latitudes en las que el panorama meteorológico no es estable durante mucho tiempo, y menos aún en primavera, por lo que seguramente pronto las cenizas se dirjirán hacia el Atlántico o hacia América en vez de hacia los cielos europeos. Serán los meteorólogos los que nos digan esto en los próximos dias, pero en cualquier caso habrá que tener cuidado, porque aunque mejore la situacion, el ir y venir de las borrascas puede hacer que a medio plazo volvamos a tener cenizas sobre Europa.
Este tema es de "Loquillo y trogloditas" y se llama "el pupitre de atrás".
Representa bastante bien la actitud que tenían los "gamberretes" en los años 80, con inquietudes que no coincidían con las que los profesores quieren para ellos: salir con chicas, ir al billar, hacer novillos,...
Sin embargo, por otro lado, aunque le fastidiaba que "el dire progre" les mandase tareas, las hacía, porque dice que por culpa de eso no puede estar con sus chicas. Así que en esta época había una combinación de rebeldía y responsabilidad, y cuando les decían que hiciesen algo, lo hacían.
¿Crees que hoy en día esta canción puede representar a la juventud, o al menos a parte de ella? ¿Han cambiado los valores en estos últimos 25 años? ¿Echas de menos tu época de gamberrete juvenil?
Espero vuestras respuestas.
