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lindsh23

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Everything posted by lindsh23

  1. During my pursuit of wormhole knowledge, I came across an article by Stephen Hawking discussing his research and opinions on wormholes and travel. I actually found the article quite interesting (and even humourous!), and felt that his findings should yield a separate blog post. While Hawking definitely believes the data that wormholes exist as a connection between different parts of spacetime, he definitely does not believe in time travel using these wormholes... ever. He states that most wormholes are only billionths or trillionths of centimeters long, not nearly large enough to fit a human, let alone an entire space crew. Wormholes are far too unstable to enlarge by any means, he believes, and even if humans could create a wormhole, it would be far to unstable to leave open long enough to travel through. Stephen Hawking is also a strong believer in paradoxes. He believes paradoxes caused by wormhole travel are one of the major reasons it could never work, even if the wormhole was large and stable enough to travel through. His example demonstrating paradoxes in wormhole travel involved a scientist looking back at himself minutes earlier through a wormhole; if he decided to shoot himself, who would be the one shooting? It would be a paradox. And this type of paradox is why time travel through a wormhole could not work. It would violate the very theory that cause comes before effect, the theory that governs the universe. In the end, the universe would descend into chaos if time travel through worm holes was possible. And according to Murphy's Law, if that could happen... it would. Hawking also points out that feedback would prevent wormholes from long term existence. As a wormhole expands, it would suck in more natural radiation, which would create a loop of radiation absorption that would eventually cause the wormhole to collapse. However, Hawking does see time travel using a black hole as a more possible alternative (although not entirely possible). At the center of the galaxy lies a supermassive black hole, and the gravitational pull around it is so strong that it slows time around it. Flying a space ship around the black hole would cause time to move substantially slower for passengers, which would make the crew travel into the future as they return to Earth. However, it is difficult to do so because the ship would have to travel the speed of light to avoid being sucked into the black hole, which is 2,000x faster than the fastest human space travel. If this were possible, however, there would be no paradox. Space travel is quite the debated topic in the science community! I will leave the link at the bottom, since it is an excellent article with some fascinating information! Until next time, Fizzix communtiy, until next time. http://www.dailymail.co.uk/home/moslive/article-1269288/STEPHEN-HAWKING-How-build-time-machine.html
  2. I finally watched the movie Interstellar! I have been meaning to watch it, since I have a closeted interest in space and quantum physics, and it was well worth the wait. While some of it was far fetched, it was very interesting and thought provoking, and I thought it was really well done! Since I recently watched the movie, I’ve decided to look into Wormholes, a concept the movie actually focused on as a form of space travel. In Interstellar, Matthew McConaughey travelled in space in hopes of finding another planet, similar to Earth, that humans could live on and populate. Since the planets he was looking into were so far away, beyond our universe, his space crew utilized a wormhole to travel that distance. So, what is a wormhole? A wormhole is a “secret passage†to other places in space-time. Space is not actually flat, it can bend and be distorted and even change as time goes on. A worm hole is simply a bend in space time, and a hole exists there which allows a shortcut to occur from one place in spacetime to another. It was named a “wormhole†because Princeton physicist John Wheeler, one of the early physicists investigating wormholes, saw this shortcut as a worm eating its way through the core of an apple. This shows the concept of a wormhole travelling between different locations of spacetime. The structure of a wormhole makes what the space team in Interstellar did rather difficult, if not impossible. The wormhole is unstable matter, and the gravitational effect of the slightest drop in mass would cause the wormhole to collapse, leaving space traveler trapped within the wormhole. Also, there is a high possibility that on the other end of the wormhole could lie a black hole. Imagine finally making it to your destination, only to be sucked into a black hole and completely decimated! In order to keep the wormhole open, negative mass, called “exotic massâ€, would have to be positioned near the mouth of the wormhole – however, exotic mass is only theorized, not discovered. A wormhole could also be created, but the mass required to penetrate spacetime in that matter would be roughly equivalent to an entire galaxy. If a wormhole could possibly fit a human successfully, creating time travel would be another story. In order to be transported to another place in time, one end would have to be sped up to nearly the speed of light, while the other end remained unaffected. This way, when the traveler travelled through the wormhole, they would emerge hundreds of years earlier on the other side of the wormhole. In order to overcome this obstacle, we would have to be able to manipulate speed and time. The concept of bending spacetime to accommodate wormholes is rather fascinating, and while it does include some scientific fact and theory, the idea seems a little far fetched at the moment. Who knows what the future will bring! Until next time, Fizzix community, until next time.
  3. Quantum physics leaves some of the craziest theories floating out there, between relativity, gravitational lensing, and black holes. But... what about virtual particles? Particles that can exist one second, and disappear in the blink of an eye? Well, physicists have discovered it. It's called the quantum foam effect. How can this be? Well, beginning with the big bang, we know that when particles expand, electrons are shot away from each other. This shooting motion does not just include the electrons, but also the photon exchange which occurs between the two. A photon must be emitted in order to scatter electrons. In order to follow the laws which govern the universe, energy and momentum conservation must be conserved during this emission. However, when the momentum conservation is calculated between the 2 electrons and the photon... it is found the photon actually has mass, therefore defying the laws of physics! These virtual particles have the "wrong" energy and momentum for a rapid period of time, and then they simply vanish. They are there long enough to defy the very nature of the universe, but disappear so that they do not cause any real disturbance. These virtual particles can also be explained by the Uncertainty Principle. I read somewhere that how virtual particles work can be compared to a bank loaning money and paying your bills: When you give your money to the bank, it is expected that the money you put in matches money you get out and use to pay your bills. But, in actuality, the bank loans out that money, and for a brief period of time you have a "wrong" amount. The more money loaned out, the less time the money has to be "wrong" before you notice. Virtual particles act the same way: the larger they are, the less stable they are, and the less time they exist. These virtual particles appear all over the universe! That "empty space" that we think exists beyond our Earth? That vacuum? In actuality, it is filled with little bubbles of particles coming in and out of existence; hence, the name "Quantum Foam". Quantum Foam was discovered because all of those virtual photons create wave energy, since photons have wave-particle duality. The magnetic field of empty space was actually measured to be about 0.01% off of the estimated value of what would have been actual empty space, which was enough to prove that something strange was happening out there. Virtual Particles also play a role in Hawking Radiation. Instead of becoming a massive photon, virtual particles can also exist as another electron and a positron. When quantum foam exists near the event horizon of a black hole, one of the two particles of the pair could get stuck in the black hole, while the other escapes, creating the radiation Steven Hawking had been trying to prove. Over time, more and more energy would escape than is captured, causing the black hole to evaporate. Quantum foam is so interesting to me because it ties together many of the quantum topics I had researched for previous blog posts. Imagine all of the virtual particles floating around in space, only to disappear and never return fractions of a second later! That is all. Until next time, Fizzix Community, until next time.
  4. You may have read the title and thought this was some weird Star Trek garbage, but it is true... at least in theory. The ever so slight possibility of teleportation is all due a concept called Quantum Entanglement. To begin, let's look at the definition of quantum physics. While Newtonian physics looks at a method of studying the Earth on a large scale: by this, I mean F=ma, KE=(1/2)mv^2, types of equations that explain the motion of large scale objects, like balls, people, and objects. Quantum mechanics, however, investigates the universe on the microscopic level. When objects get very small, like subatomic particles, their behavior begins to differ from the Newtonian model and move toward the quantum model. Now that we have that straightened that out, what even is quantum entanglement? In chemistry, we learn that each electron in an atom has its own energy level, orbital, and spin to approximate its location and direction. Very typical. However, in very rare cases, if an electron becomes paired with another electron that is identical (same level, orbital, and spin), they are, in fact, the same particle. This phenomenon is near impossible to impossible by theory, however, due to Hund's Law. Hund's Law states that electrons cannot exist with all quantum numbers the same, meaning they can't have the same everything (spin, energy level, orbital). If it were to occur that two electrons were identical, the fun part comes. If this were to happen, things get complicated because these electrons now stay the same no matter what. This means that when one electron changes spin or location, so does the other. No matter where the other is. BOOM. Teleportation. This other electron can be changed or transported anywhere without any outside influence whatsoever. As I wrote before, Hund's Law makes this near impossible, but this theory exists, and teleportation has a beginning! Quantum mechanics always blows my mind, and I hope it interests you too! Until next time, Fizzix Community, until next time.
  5. I'm thinking this will be my last post about my museum trip, but this is about my favorite presentation we watched there. The last presentation we saw was one on fiber optics, which are on the cutting edge of optical, digital, and even medical technology. What is a fiber optic cable? Fiber optic cables, or lines, are optically pure strands of glass that are the thickness of approximately a human hair. These lines are used to transmit digital information over long distances, and its main current use is carrying internet bandwidth. These are also used as a visual mechanism in minimally invasive surgery. How does fiber optic cable relay these messages? It all has to do with an old physics concept: Snell's Law. How the message stays trapped in the fiber optic cable is all about the index of refraction. Because the index of refraction of the cable is stronger than the air around it, the light stays trapped within the cable and travels the entire length. Also, because the optical glass is one of the purest forms of glass availible, the beam loses very little of its strength as it passes through the glass. As a result, digital messages can be relayed through light passing through miles of fiber optic cable. Fiber optics can also be used for medical procedures, as suggested earlier. Fiber optic tubes with cameras on the end can be inserted into the abdomen during a surgical procedure, or wherever the surgery sight is, and the surgen can use the image passed through the cable to conduct the surgery without completely cutting the individual open. Because of this visual ease, many surgeries only require 3 small incisions, one fiber optic incision and 2 for the surgical tools used for the procedure. Fiber optics have provided a much simpler and effective way to transport all different types of digital messages. Fiber optical cables are being improved all the time to increase the bandwidth they can carry and to prevent communication errors, which have already been substantially decreased by the conversion to fiber optics. Next time you use the internet, remember that all of that information is being passed through tiny strands of glass! Man, how technology has changed! Until next time, Fizzix Community, until next time.
  6. As you may have previously read, my recent trip to the Corning Museum of Glass has left me pondering the physics of glass. If you have never been there before, the place is really neat! The museum is laid out with tons of interactive exhibits, as well as opportunities to hear presentations about the science of glass from people at the museum. You also have the opportunity to create your own glass creation... which is what I will be discussing in this blog post! When I went, I made a glass flower: this includes a curly, solid glass stem with petals which branch out from that stem. However, it was glass forming, not glass blowing. The glass maker started off by gathering a lump of hot glass onto a rod, and let me roll the rod back and forth in order to distribute the glass into a spherical, smooth lump. Why does glass so easy do this? Glass is a unique solid because instead of having a rigid, crystalline structure, the molecules are able to slide past each other, allowing it to "flow" yet stay solid. These molecules are easily formed, through working and forming, into structures including my flower. After I formed the lump, I then used a paddle to flatten the top of the lump, and began to roll the rod while pulling each petal out. As I time went on, it became more and more difficult to pull the petals out. This was due to the cooling of the glass. Heat energy was escaping the glass into the atmosphere, and as the heat energy left, the molecules experienced less motion. Although glass is different than other solids in the fact that it "flows", this loss of energy caused the particles to become more stationary, and therefore more difficult to move their structure. After forming the stem, the glass maker placed a score mark on the glass, and giving the rod a tap, the flower broke smoothly from the rod; this was due to the stress on the glass, as I explained in my previous blog post. Since the score placed a lot of stress on one concentrated area of the glass, the glass easily separated with stimuli at that point. The flower was then placed into a kiln to cool overnight. Why a kiln?, you might think. Going back to my previous post, it is rather simple: the glass needs to cool evenly in order to prevent excessive amounts of stress, and gradually cooling the glass from its initial temperature in a controlled setting is the best way to do so. The glass maker showed what could happen if the glass wasn't cooled in the kiln by heating a piece of glass and putting it directly in cold water. The glass shattered because the rapid temperature change caused rapid tension on the glass, putting it under pressure it could not withstand. After my trip to the museum, I was glad to have a piece of work I could bring home with me! (Or rather, have mailed home!). Until next time, Fizzix Community, until next time. My flower!
  7. A few weeks back, I went to the Corning Museum of Glass, somewhere I have been meaning to go. I had never been there before, and although the car ride was rather long, it was well worth the trip! On top of the many exhibits, there were multitude of presentations given by the museum staff on the science of glass. Since I went to a few of these demos, I will write a few different posts on each of these topics. The first one we went to see was on the science of the structure of the glass and how it impacts the way it shatters. The instructor started off by heating a typical glass cup in one area, and placing it in a polariscope, which showed the places on the glass where the glass was experiencing stress. Stress is where the glass is weak, and the heated area of the glass was the most stressed. After, he heated evenly in a ring all around the glass, and when he tapped the glass, it cleanly broke at that point. This was because the ring was where the glass was the most stressed. Different types of glass are heated differently and made out of different materials in order to change the stress of the glass, and therefore change its strength. Typical window glass, or annealed glass, is thick, and while the heating of the glass is somewhat even, it is not nearly as precise as other types of glass, making it shatter easily upon impact. Also, since there is irregularity in the placement of the stress, the glass shatters into random fragments, as one can see when a window is broken by a baseball or in a robbery. Tempered glass is a stronger type of glass, also known as safety glass, where the heating and cooling process is much more regulated. The glass is heated evenly, but then cooled rapidly (in a matter of seconds). How does this create strength? The outer surface of the glass cools much faster than the inside, and as the center of the glass cools, it tries to pull away from the outer surface; this creates tension on the inside, while the outer surfaces compresses with great strength. Compressed glass is much stronger than glass in tension since compressed glass resists breaking apart. Car windshields are another application where the glass used needs to have extra strength. However, this type of glass is different. Upon impact, the glass in a windshield shatters, but stays in place. In severe impacts, like a head to the windshield or a bullet, it even appears as if there is a solid in the glass. How can this be? Windshield glass is actually two pieces of tempered glass with a piece of plastic laminated between them. The layering affect makes the glass strong, while the plastic in between prevents glass fragments from flying and injuring those in the accident. It’s crazy how much heat can affect the strength of glass! One mishap with cooling can change a durable piece of tempered glass into glass which easily shatters. The product of that day at the Corning Museum of Glass was a new knowledge of how glass shatters and a lot of broken glass! Soon to come is more of my trip to Corning! Until next time, Fizzix community, until next time.
  8. Throughout my physics carrier, forces caused by a field have been rather prevalent in my calculations. I mean, the force due to gravity appears in most mechanics problems. But what really is a field? I have seemed to feel that a field is a word for a certain force that scientists can't really explain. "hey, why do things fall to the ground on Earth?" "I don't know... why don't we just call it a field!" So, I decided to take a closer look at force fields and their impact on physics! What is the definition of a force field? A force field is a vector field describing a non-contact force on a particle in various positions in space. Such examples, as you may know, are the gravitational field and the electrostatic field. A force field is not what you see in the movies: a super power which creates a shield to protect you from any and all harm. I can tell you, Violet from the Incredibles was not projecting a gravitational field around herself! To be honest, it seems to be difficult to find information on forces applied by fields. Fields are such a perplexing concept because no physical object or surface has to apply the force in order for it to exist... it comes from strange internal sources, such as the mass of the earth or the electron charge of a particle. The only real way for fields to be represented, other than seeing them in action, is through field lines - vector line portrayals of the motion of particles in that field. If only there was more tangible evidence as to how and why fields exist. But I guess that's a question that new generations of physicists will have to investigate... so many discoveries have been made, and they need some questions to answer too! So, for now, the mystery of field forces remains Until next time, Fizzix community, until next time.
  9. Solids, liquids, and gases... all the typical phases of matter we have investigated since we learned about the water cycle in elementary school (evaporation, condensation, precipitation!). Since then, states of matter have been investigated in middle school science class, biology, chemistry, and physics. However, scientists are moving toward the forefront of discovery in trying to establish a new sort of state of matter. This new state of matter is called quark-gluon plasma, and is being experimented with in a particle collider in Long Island. In this state of matter, the separation of parts would get down to the miniscule parts of the atomic structure: protons, neutrons, electrons, even the smaller quarks and gluons. This plasma is a mixture of free flowing quarks and gluons that exists at extremely high temperatures and densities in a laboratory setting. The difficulty in forming such a substance is that quarks are incredibly sociable and are difficult to keep independent, since they switch between "types" constantly. It is believed that when the Big Bang occurred, all matter existed for milliseconds as quark-gluon plasma. Why create a new state of matter? Why go through all the trouble to split up some silly quarks? The answer lies in types of matter and energy. Once created, there is a possibility that quark-gluon plasma can transmute into new forms of matter or energy that can be harnessed and studied. These phase transitions can also reveal new information on forces of nature, including electrostatic force and weak and strong nuclear forces. There ya have it: new states of matter! Until next time, Fizzix community, until next time.
  10. Many of you are probably familiar with Stephan Hawking, the brilliant physicist confined to a wheelchair (in fact they just made a movie about him, I'm very interested in seeing it). Hawking is known for his theories and discoveries in the realm of relativity and space, especially concerning black holes. One of his discoveries that I would like to discuss is Hawking Radiation. Hawking Radiation is the black body radiation a black hole emits due to quantum effects near the event horizon - or the boarder that prevents activity in the black hole from reaching an observer. Due to the uncertainty principle I discussed before, a rotating black hole should create and emit particles, causing the black hole to lose mass, shrink, and eventually vanish. This is called black hole evaporation. Micro black holes are larger net emitters of this Hawking Radiation than large black holes, and are expected to dissipate faster. Previously, it was believed that the gravitational strength of a black hole was too strong to let nothing, not even electromagnetic radiation, escape. However, with the discovery of Hawking Radiation, it seems that black holes create particle-antiparticle pairs, and due to vacuum fluctuations in the black hole, the pair appears near to the even horizon, and one particle escapes while the other falls into the gravitational attraction of the black hole, making it appear to the observer that a particle was emitted. These emissions cause a loss in mass for the black hole. Hawking's theories challenged previous models of the black hole and brought to light new connections between gravity and quantum physics. I hope y'all find quantum physics as interesting as I do! Until next time, Fizzix community, until next time.
  11. Think of the entire human race: hard to fathom, isn't it? Around 7 billion people of all different races and walks of life spread throughout globe. Okay... this is anthropology, not physics. WRONG! Instead, I am going to look on the atomic level of human life. While the basis of the atomic model was being shaped and formed, scientist Ernest Rutherford conducted a gold foil experiment which proved that the atom is composed mostly of empty space.... Over 99% of the atom. While the nucleus exists in the center of the atom, electrons orbit at such a distance due to repulsion that creates the empty space of the atom. Back on the topic of humans, think about how each human is made up of trillions of atoms, bonded together to form cells, fats, proteins, and other important molecules and substances. There are over 10e27 atoms in each human being. Now, take all of the atoms of the entire human race. If one took away all of the empty space for each atom and heavy-duty compressed the nuclei and electrons together... the super-atom would fit into the size of a sugar cube! That is how significant the empty space of atoms is! Due to the high density of this cube, it would weigh approximately 5 billion tons... of 10x the weight of the current human race! To connect this to other physics topics, this is the sort of act that happens after certain supernovas, or explosions of stars. Supernovas form neutron stars, or a super-dense massive leftover of a previous star. There you have it, the strange fact of atoms in the human race. Definitely something new for me also! Until next time, Fizzix community, until next time.
  12. I seem to be on the topic of strange theorums, and I am definitely adding to this streak since I will be discussing the Anthropic Principle. What could this principle possibly mean to science? Well, Anthropic means "pertaining to man kind", and this principle follows suit. The principle was first devolved by Australian physicist Brandon Carter. The principle centers around the idea that human life is so phenomenal in science that it cannot be overlooked, and the entire universe is centered around human growth and life forming characteristics. Why doesn't electrostatic repulsion play a larger role than nuclear bonds, making atom formation impossible and preventing human life? Carter argues why in his 2 evolutions of the Anthropic Principle: Weak Anthropic Principle: Observed scientific values must be able to allow there to exist at least one region of the universe that has physical properties allowing humans to exist, and we exist within that region Strong Anthropic Principle: The universe must have properties that allow life to exist in it at one point. Carter argues that the universe was formed the way it was, with such carbon based life, because the intention was for human life to exist somewhere. He later came out with an even more controversial statement: Final Anthropic Principle: Intelligent information-processing must come into existence in the universe, and once it comes into existence, it will never die out. These statements are a way of explaining human involvement in the science and makeup of the universe. Supporters of the anthropic principle state that our very existence changes the course of life and the environment we live in, causing the universe to bend toward us. The makeup of our planet, space, and nearby galaxies could potentially be explained by such a principle. Humans themselves are selfish in nature, but to think we are the reason the universe exists... well, that is just one crazy thought! Think about how important your existence is to the state of the universe tonight until next time, Fizzix community, until next time.
  13. As I discussed in my last post, the Observer Effect remains a frequently pondered and strange phenomenon of quantum mechanics. However, people have often mixed up the observer effect with the Uncertainty Principle, a different but related quantum physics concept. The Uncertainty Principle, developed by Werner Heisenberg, states that the more precisely the position of a particle is known, the less precisely its momentum is known (and vice versa). This happens because when the wavefunction of any particle (refer to gravitational wave post: EVERYTHING IS A WAVE!!) is expressed in these units, position and momentum become conjugate variables of each other. Wow... a lot of complicated jargon. Let's try to get through this: Every particle is also a wave, as stated in de Broglies theorem, and can be expressed by a wave function (x,t). A probability density function is used to find a ballpark range of a location with the integral of the wave function. This probability is very slim, since the wave packet, or probable location of the particle, is large compared to the size of the particle. However, this can also be written as a summation of all of these wave functions in the nearby area, making the position of said particle localized due the multitude of waves. However, while the position is becoming more localized, the momentum is proportionally becoming more delocalized, with this massive sum of waves having a plethora of momenta. This is the basis of the uncertainty principle. As both the uncertainty principle and the observer effect have shown, quantum mechanics is incredibly abstract and intricate, and I hope you have seen a bit into the uncharted territory of quantum mechanics! Until next time, Fizzix community, until next time.
  14. In Physics last year, we watched a video regarding quantum physics, since the topic was so new to any of us. In this bizarre video, I remember being perplexed by a phenomenon known as the observer effect. As I listened to the video explain how observation of a system affects the system itself, I began imagining living particles watching for human observation in order to change their behavior... It really blew me away. The Observer Effect, in its basic form, is when changes in observation of a system cause changes in the phenomenon being observed. How, you may say, can observing a system change the system itself? In its most basic form, the observer effect can be observed (no pun intended) when one checks the pressure on a tire, since it is difficult to do so without releasing some air and therefore changing the system. On the particle level, electrons are often observed for data in physics. Electrons are detectable only when they interact with a photon, which would cause the electron to defer from its original path. The scientist will then never know what the electrons true, intended path was. Quantum Mechanics is where the observer effect starts to get complicated. The Quantum Zeno Effect, or the Turing Paradox, can be linked back to the observer effect. This states that a quantum system left unobserved will decay, while a quantum system under continuous observation will never decay; the evolution of the system is "frozen" because it is observed frequently enough in its initial state. Each measurement causes a wavefunction collapse, freezing that measurement in time. In such cases, even a microscopic piece of observation technology performs and is recognized as an "observer", making it difficult to take outside involvement out of quantum measurements. The Observer Effect is often confused with another concept called the Uncertainty Principle, which I will discuss at a later time. Quantum mechanics is a messy world compared to Newtonian physics, and the observer effect does not make it any easier. There is still much to be learned about quantum systems and their reactions to outlying stimulus. To believe this all stems back from a short video junior year! Until next time, Fizzix community, until next time.
  15. This was a very Madge post and I loved every second of it... Bravo.
  16. Tonight, I began to ponder a strange thought... what if the strength of the gravitational field was as strong as the electrical field, and vice versa? I mean, the difference is quite drastic. The Earth's acceleration due to gravity is 9.81 ms^-2, while Coloumb's Constant is 8.99e9 Nm^2C^-2... which, as you can imagine, leads to quite the drastic change in strength. A person of 60kg experiences a gravitational force of 588.6 N... around 132lbs. But what if we were to replace g (the acceleration due to gravity) with k (coloumb's constant)? This person would instead experience a force of 5.394e11N!! This is such an INSANE amount of force that would completely obliterate a human being. To put things into perspective, a typical person can experience about 5 g's of force before passing out; this means that said person could experience about 2943 N of force. An experienced pilot wears a G-suit when flying and is trained to strain their muscles to avoid the passing-out response to high amounts of g-force, since they nose dive frequently. Experienced pilots can typically take up to 9 g's of force, meaning this person could take about 5297 N of force... still well off of gravitational force with coloumb's constant. Soon after these thresholds are reached, symptoms including grey outs (loss of hue in vision), blackouts, red outs ( red vision due to bursting blood vessels in the eyes), loss of consciousness, and death occur if the body is not leveled out quickly. Replacing the constant g with k would be detrimental to mankind... no human could survive that kind of force and would be completely crushed, if not nearly vaporized. Be thankful that gravity exists at the strength it does... I'm pretty sure that no one wants to be crushed by a force of 5.394e11N! If the roles of the gravitational field and electrical field were switched, and I am quite sure the outcome of life would be much different than it is today. Until next time, Fizzix community, until next time.
  17. As I pondered what to write about for this blog post, I began to consider a topic that we touched upon in Physics B: thin film interference. I really never understood thin film intereference last year... as a matter of fact, there was a thin film intereference free response question on the AP last year and I just stared at it in a very confused manner. So, I figured I would take a second look at it this year. Thin film inteference happens when the upper and lower boundaries of a thin film, such as a soap bubble, both reflect light waves and their interference becomes a new wave. This occurs because the film is so thin, making the boundaries of the substance incredibly close to each other. For thin film diffraction to occur, the medium must have a thickness in sub-nanometers or microns. Interference is constructive (or creates a new wave) when the difference of optical path is an integer multiple of the light's wavelength. With a monochromatic light source, the interference appears as light and dark bands... But, when the source is broadband, like the sun, the interference appears as multiple color bands - hence the rainbow glare on bubbles and oil on the road. Oil is slightly different than soap interference. Oil sits atop a layer of water, and has an index of around 1.5. Constructive interference occurs when the difference of optical path is an integer multiple minus 1/2 multiplied by the wavelength. There you have it... thin film diffraction in its finest. I'm glad I understand it after I needed to use it in Physics B! At least I learned it eventually, and now you all know why oil on the road looks rainbow! Until next time, Fizzix community, until next time.
  18. I am really good about managing my time and blogging, as you can see... But I figured I would talk about the physics behind... BOMBS!!! I mean, nuclear warfare (at least in theory) has become every-so-popular after the Manhattan Project in the United States for World War II. I figured it is only fair to address it for all the physics glory it deserves. Now, nuclear bombs can be split into two categories: bombs based on nuclear fission, and bombs based on nuclear fusion. However, both involve some sort of nuclear fission reaction at some point in the progress of the chain reaction (since that is all bombs are... one big, fun chain reaction!). First, lets address nuclear fission bombs. Nuclear fission bombs can also be split into two subcategories: uranium bombs and plutonium bombs. While U-238 is the most commonly occurring isotope of Uranium (92 protons, 146 neutrons), U-235 is the most valuable for nuclear weapons. On average, the fission of U-235 produces about 2.5 neutrons. A complete chain reaction of the fission of 50 kg of U-235, the approximate amount of Uranium in the bomb dropped on Hiroshima, could yield 500 kilotons of fissioned material. However, only 3% of that yield was achieved, given that most of the U-235 was dispersed in such a way that was spread to thin to continue the reaction. In order for the chain reaction to begin, the U-235 must reach a critical mass density. This is done by splitting such a critical mass of U-235 in half and placing each half on one end of the bomb. Then, when the bomb is ignited, half of the Uranium is shot like a bullet toward the other, creating a chain reaction, and therefore a nuclear explosion! A plutonium fission bomb works in a similar manner, using Pu-239 instead. However, a plutonium bomb is harder to ignite. The plutonium is modelled like a spherical core, the "plutonium pit", and placed in a shell of high explosives. When the explosives all detonate at the precise time, it forms a spherical shock wave, which creates such an extreme pressure that the plutonium core is compressed to critical mass density and begins its chain reaction. Plutonium bombs are preferred, once mastered, since only 10 kg of plutonium is necessary for a reaction. For fusion bombs, the hydrogen bomb is the name of the game. In order to begin the fusion reaction in a hydrogen bomb, a fission bomb needs to take place first in order to generate the high energy needed for hydrogen fusion. While normal hydrogen contains one proton, Deuterium is hydrogen which contains one proton and one neutron, and is preferred for a hydrogen fusion reaction. In a fusion reaction, deuterium and tritium, hydrogen with 1 proton and 2 neutrons, combine to create helium, a neutron, and energy. This causes lithium, also in the bomb, to combine with that neutron and create helium and more tritium and energy. This creates a chain reaction of creation and massive amounts of energy. When the warhead, a plutonium core fission bomb, is ignited in a fusion bomb, the fission emits x-rays, which reflects along the inside of the casing around the material for the fusion reaction, turning polystyrene foam into plasma, sparking another plutonium fission reaction. As the lithium deuteride is heated and compressed, it reaches the energy necessary for fusion, creating a massive explosion. This explosion is much more powerful than fission, creating massive amount of energy. It's crazy that even as far back as World War II, scientists were investigating the physics around these nuclear phenomena and harnessing it for weaponry! What an amazing feat combining physics, chemistry, and technology! Until next time, Fizzix Community, until next time.
  19. As a wannabe cardiothoracic surgeon, I find fluid mechanics of the cardiovascular system to be fascinating. I believe one of the greatest accomplishments in medicine is the ability to implant an artificial heart into a patient, since the heart is such a complex organ and one of the most vital to the function of the body. The intricate physics necessary for an artificial heart to function properly must be precise, and its applications are lifesaving. The human heart consists of four chambers: two atria and two ventricles. Blood comes into the right atrium, then is pumped into the right ventricle, which brings the blood to the lungs to be oxygenated. It comes back into the left ventricle, and is then distributed throughout the body by the left atrium. These are all connected by valves, so the cardiovascular system is a one way fluid system powered by the pressure created by heart contractions (diastolic and systolic pressure). Above is the diagram of an artificial heart, which replaces the human heart with four man made chambers replacing the atria and ventricles. Tubes connecting to these chambers supply air to balloon-type structures within the artificial chambers which inflate with air to simulate the pressure created within the chambers as a human heart expands and contracts. Utilizing these balloons, the artificial heart can maintain the pressure needed to constantly force both the oxygenated and the nonoxygenated blood through the body. What I believe to be the most incredible physics phenomenon of this machine is the way it can receive power externally without any skin penetration. An electronics pack is inserted into the patient's abdomen during surgery. This pack receives power by connecting an external power source to a coil of wire, which creates a magnetic field; this magnetic field then induces a current in a second coil implanted under the skin, which changes the alternating current to a direct and usable current. This way, the chance of infection from wounds in the skin is reduced. An artificial heart also has many challenges and complications. The heart has to be carefully constructed so that it is incredibly efficient; otherwise, extra power is dissipated as heat, which can damage the tissue surrounding it and be fatal. The mechanism also has to be carefully placed so that it is not displaced by patient movement. The artificial heart can measure the amount of blood flow, which is important when the patient engages in physical exercise and needs to pump blood faster. The blood flow monitor in the artificial heart uses ultrasound to bounce sound waves off of the blood cells coming out of the heart, finding the blood flow without any invasive contact. The use of artificial hearts is absolutely incredible, and the physics behind it is vital and complex. The use of such artificial devices is like "playing god" in medical ethics, but its results are outstanding.
  20. So as this quarter comes to an end, of course I am scrambling to finish everything and feeling the stressed. So what better to relieve said stress? Popcorn, of course! After watching popcorn pop endless times throughout my life (especially the exciting Jiffy Pop!) I suddenly thought of the physics behind a kernel of popcorn popping tonight, so I decided to look further into it. The purpose of microwaving popcorn or placing it over heat is to heat up the water inside of the popcorn kernel. Individual popcorn kernels have moisture trapped inside of its hull, and as it heats up, it begins to boil once it reaches 100 C. The boiling of the water inside of the kernel causes pressure to build within the kernel, since the water vapors gain kinetic and potential energy within the concealed kernel. Not only does the water vapor cause a rise in internal pressure, but it also causes the starch within the kernel to soften and expand, creating even more pressure on top of the vapor pressure within the kernel. The wall of the kernel also begins to melt at such high heats, causing it to weaken as the pressure increases. The pressure at this point can be up to 9 times as high as the atmospheric pressure. Under this massive pressure, the wall of the kernel bursts, and the starch explodes outward. Ever notice how not all kernels are popped in a bag of microwave popcorn? That's because the amount of moisture in the kernel needs to be just right for this explosion. If there isn't enough moisture, the kernel cannot build enough pressure to explode. If there is too much moisture, the wall of the kernel melts before the pressure is high enough for a good starch explosion. Once the kernel explodes, the starch pressure immediately drops, and the steam carries a film of starch outward. This expansion of starch is what creates the explosion starch cloud we know as popcorn. So there you have it! I overthought the simple popping of popcorn so you guys don't have to! Until next time, Fizzix Community, until next time.
  21. Quantum physics is definitely a fascinating topic... being able to investigate behavior at the particle level is so cool! I would definitely want to take a class on it in college!
  22. Check out my post on cloaking devices... not quite an invisibility cloak, but that definitely was my inspiration
  23. Today in AP Chem, we began to discuss the behavior of electrons, most specifically, in regards to light and light energy. Most of what we looked over was old news from Physics last year, as far as the relationships between speed of light, frequency, and wavelength. However, this equation brought back some ideas that we looked at last year: We often times looked at this equation in Physics-B to analyze matter-wave duality, since light behaves both as a wave and as a particle, known as a photon. Light is transmitted in waves, like energy, but also carries momentum due to the fact that it possesses particle properties (the mv of the equation above). I always found it rather humorous last year when we did practice problems involving the wavelength of a rather massive object, clearly not a sole form of energy travelling in waves - such a problem I recall involved a bowling ball. Let's find the wavelength of myself, shall we? Let's say I am strolling along one day at about .5 m/s (I am not sure what speed the typical human travels at). My mass is approximately 58 kg. Using Planck's constant and the equation above, my "human wavelength", as I like to call it, can be calculated: wavelength = 6.63e-34Js/(58kg*0.5m/s) = 2.286e-35m So, what does this mean? Well... basically nothing. Said "wavelength" has such a small magnitude that it is insignificant. A human is obviously a human, and not energy. This equation comes into play at the quantum level of physics. Since light is soooooooo tiny compared to a human, such changes between wave and particle properties can be detected: thus, light is able to have momentum, yet also travel in transverse waves. Could you imagine a human performing double slit diffraction? Neither can I. Those would have to be two interesting looking slits. Basically, I just think that matter-wave duality is pretty cool. Who knew, years ago, that light could live in both the realm of wave and particle? Oh well, just something to think about. Until next time, Fizzix Community, until next time.
  24. lindsh23

    #tbt

    On this Tuesday, I figured I would offer a nice throwback for everyone... Bill Nye! But not Bill Nye the Science Guy that we typically see... I found a physics video with a serious Bill Nye (I know, strange right?) The video is rather long, about 45 minutes, but I focused on about 5 minutes of it (about 1:30-5:54 if you are tuning in from the link above). Nye talks about an older theory of Aristotle's, which stated that objects of different masses fall at different velocities due to their mass. That theory was later challenged by Galileo, who said that heavier objects only seemed to fall faster due to air resistance... this relationship makes sense, since this year we learned that the terminal velocity of any object is directly proportionate to its mass. Even Galileo, many years ago, understood how air resistance messed with theoretically "perfect" physics models. Air resistance makes algebraically based physics difficult to work with in real world situations, since the air around us creates opposing forces daily (sorry Powlin!) The video also shows a chamber at a NASA research building which, against the odds, reverses most effects of air resistance for testing purposes. For testing for equipment sent to the International Space Station, all air is sucked out of the chamber, and objects are dropped and tested with a lack of air resistance. I was kind of hoping they would drop the ball and the feather they were using as a demonstration in the beginning of the video... Oh well, I guess I will have to find my own chamber to test my curiosity! In conclusion, I would have to say that air resistance is a pretty big part of application physics (and also a big pain in the butt!) Until next time, Fizzix Community, until next time.
  25. Look up "rogue black holes"... they are a fear of mine
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