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PaperBoy

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  1. PaperBoy
    I'm an AP Physics C student who loves to be silly and goof around whenever I can. I enjoy physics, mathematics, astronomy, programming, engineering, swimming, definitely not cooking, listening to music, and Super Lawn Chair Fighters 3000. My favorite music genres are rock, alternative rock, and heavy metal (though there aren't many good heavy metal bands in my opinion, just a lot of screaming). Since I was maybe 9 years old I've wanted to be an astrophysicist, and that hasn't really changed. I'm taking this class to further my knowledge in an area i truly enjoy studying, unlike most of school. Even if I don't end up using it for a career, it's still a very conceptually crazy course. I hope to actually start learning some cutting edge physics this year, instead of been-there, done-that. I'm excited to start learning physics again in general, though I'm still a little scared I might not be able to keep up. I'll make it! Adios.
  2. PaperBoy

    Call of Physics

    By PaperBoy,

    I'm sure everyone reading this knows what a sniper rifle is. You know: long barrel, cylindrical scope, big long bullets, used for long range and heavily armored targets. But, what you might not know is how powerful one is. The standard NATO sniper rifle bullet is the .5 BMG. Made in 1921, the most powerful version of that cartridge is about .052 kg, and leaves the rifle at 882 m/s. p = mv, so p = (.052)(882) = 45.86 Ns. That big fat hunk of copper has about 50 Ns of life in it. Now, the average adult human head weighs about 4.5 - 5 kg. Seen as how I'm writing this I'll use myself as the test subject. I'm not quite an adult yet, so let's say 4.5 kg. One day, a friendly physics teacher near you sees just way too many tests in one day, pulls a standard issue sniper rifle out of his attack and takes a pot shot at some weird kid. Naturally my head pops of like a tootsie pop in that owl cartoon. Assuming the bullet finds a warm new home in my cranium, that's 10.08 m/s it pulls my dome along with. The average height of a 17 year old male teenager is about 1.75 m. Assuming that the bullet is fired horizontally, we can use kinematics magic to find that my head hits the ground 6.02 m away from my toothpick body, and rolls whocares m afterwards. Doesn't sound fun does it?
    That's why I'm proud to present to you our newest innovation in protective headgear: the tank hat. This simple helmet is made of solid 6" steel and can protect you from bullets, mortar, bullies, and apples. Teach Newton a thing or two today!
    --Warning, tank hat does not protect against .5 BMG Armor Piercing rounds. Don't be rude to IHS Physics teachers for your own good--
  3. PaperBoy

    To Infinity and Beyond

    By PaperBoy,

    Recently I discovered something about Position vs. Time graphs that I found fascinating. Did you know there are far more than 2 derivatives of the relationship? Acceleration and velocity hardly scratch the surface! Here's a list for all you position fanatics out there:
    Derivative:          Name:
    -5                         Absounce
    -4                         Abserk
    -3                         Abseleration
    -2                         Absity
    -1                         Absement (Absition)
    0                          Position (Displacement)
    1                          Velocity
    2                          Acceleration
    3                          Jerk
    4                          Jounce (Snap)
    5                          Crackle
    6                          Pop
    7                          Lock
    8                          Drop
     
    Can you believe it? Mainstream cereal somehow found its way into physics class other than on a food tray. Though, in all honesty, the derivations and integrals become increasingly less useful. Few practical equations even have enough exponents to avoid from becoming 0. It makes sense if you think about it: each time a derivative is computed the exponent of all the variables is decreased by 1. Therefore, you'd need an x^8 to even see a Drop vs. Time graph that isn't a constant zero. And those look like big goofy bowls, why would you want one of those?
    In the end I guess it's not as climactic as I first assumed, but still pretty cool that position goes way beyond its most common boundaries. If you wanna find out more for yourself here's the link I found:
    http://wearcam.org/absement/Derivatives_of_displacement.htm
     
    --This blog is in no way affiliated with Kellogg's Rice Krispies(c) and does not confirm or deny the existence of tasty rice breakfast cereal--
  4. PaperBoy

    Unstoppable

    By PaperBoy,

    Einstein had some pretty crazy theories about the universe. One of his most famous may be that no object may accelerate up to or beyond the speed of light. However, few know the implications of this startling discovery.
     
    One instance put across is the idea that when an object moves faster, it actually gains more mass. This is because all particles in the universe are said to exist within a field called the Higgs Field. This field is responsible for the mass of all objects in existence. The Higgs Field is an energy field, and when an object passes through it at a certain velocity, it gains mass accordingly. Because the speed of light is the maximum speed a particle can move at, it can be seen as infinite velocity. Therefore, for a particle to move at the speed of light in the Higgs Field would mean that this particle gains infinite mass.
     
    So, what would happen if two particles approaching the speed of light hit each other head-on? They would each have near infinite mass and velocity, and therefore momentum, so who would win? It’s the age old question: “What happens when an unstoppable force meets an immovable object?” Or I guess in this case, what happens when an unstoppable force meets and unstoppable force?
  5. PaperBoy

    Electrifying!

    By PaperBoy,

    Remember those cartoon kids shows where lightning bolts sent you flying into the sky with your pants on fire? I’m talking about a Team Rocket blasting off again sort of scenario. I always thought those were pretty funny, but how would they work in real life?
     
    Let’s assume that by the Laws of Disney magic, being struck with lightning instantly converts all of its energy into kinetic energy for the object hit. So, a 50 kg cartoon character gets pegged. The average lightning bolt has about 5 GJ of electrical energy in it, and contact lasts only about 30 µs. The character starts at rest. Kinetic Energy = .5mv^2, so we can calculate the new speed of the character to be 14,142.14 m/s. Let’s say this is actually James from Team Rocket, so of course he shoots up into the air at an angle of about 75° with the ground. Using the kinematics equations this time we can find that his maximum height is about 9,510,832.84 m.
     
    I guess they were right all along: James would disappear almost instantly, like a flash in the sky. Huh.
  6. PaperBoy

    AP Spheres

    By PaperBoy,

    In my last blog I talked about the three (up to five) types of civilization as labelled by the Kardashev Scale. I also said that type II civilizations can harness the full power of their star, with something called a Dyson Sphere.
    The Dyson Sphere is a theorized invention by Olaf Stapledon. The basic goal of the project is to someday completely harness the Sun’s energy output. This includes every single Joule of especially heat and light energy the fusion within the Sun’s core creates. Naturally, this concept would require a lot of hard work to complete. There are a few different versions of his idea though, so I’ll mention each one and explain.
    One idea is the Dyson Swarm. So, one plan is to make an enormous amount of solar powered satellites which would encircle the Sun in a large ring, like a circumference. They would circle the Sun, collecting energy and even slightly altering the light that reaches Earth. The energy collected by the satellites would then be wirelessly sent back to Earth for use.
    Another idea is the Dyson Bubble. This idea basically consists of several Dyson Swarm circumferences that sit in place around the Sun instead of orbiting. They would prevent the Sun from sucking them into its core with the outward pushing radiation pressure, or the force of small particles hitting the satellites.
    The final concept is an actual sphere all around the Sun, totally taking in all its energy. However, this idea has several theoretical problems, and Dyson himself denounced it as unfeasible.
    Maybe someday we’ll finally harness all that fusion energy, but most likely not for many centuries. Until then, I guess we’ll just have to rely on renewable energy and eventually our own fusion reactions.
  7. PaperBoy

    Winter Wonderland

    By PaperBoy,

    Rochester winters are famous for their snow, and the next one isn’t far off. The more the merrier I say, except when it's that really dense, slushy snow that clogs up your driveway. Unless of course, you're using it to peg some random stranger with. But what if it breaks up like mine always do? Will it still hit the mark?
     
    Let's say we have a nice big snowball, separated into three chunks. The dense center has a mass of .02 kg. The next, slightly less dense section has .01 kg, and the outer ring is fluffy snow with .005 kg, for a total of .035 kg. It's thrown from a teenage boy's arm height - let's say 1.2 m - at a small child's head - about .5 m high. The child is 6 m away. The snowball is thrown at exactly 15.88 m/s horizontally so that it may hit the target perfectly. But, after 2 m, .005 kg breaks off, and after another 2m, .01 kg breaks off too. Using conservation of momentum, knowing each piece breaks off at the current speed of the snowball, we find the speed in the x-plane to be 15.88 m/s again! Repeating the same procedure for the next 2 m, we again find that the speed of the snowball hasn’t changed. Thus, the snowball hits its target perfectly, and the scientists involved get a stern talking to from an angry mother. Complete success!
  8. PaperBoy

    Grapple Zapple

    By PaperBoy,

    Everybody loves a good hero. But, are they realistic? Some of our favorite crusaders - Batman, Link, Green Arrow - use grappling hooks to get around. I wonder if they’d work like in the games and movies.
     
    Let’s say Batman is trying to get into Arkham Asylum to teach some no good-nicks what he thinks of this whole “rehabilitation” thing. He needs to get two floors up, which is about 6.6 m. And, like in the movies, he needs to rocket up that distance, let’s say at about 6 m/s. The average man weighs 70 kg, but Batman is pretty buff, so we’ll make it 75 kg. We can calculate the work needed to be (.5)mv^2 + mgh, which here equals 6205.95 J. We also know v = d/t, so that means t = d/v = 1.1 s. And, power = W/t = 5641.77 W.
     
    It’s pretty safe to say a handheld motor like the ones we see in the media couldn’t make over 5.5 kW of pull. A mounted artillery grappling gun could, and are used by the US special forces for stealth missions. However, until our technology evolves a bit more, Batman will just have to learn to actually fly.
  9. PaperBoy

    Fissusion

    By PaperBoy,

    Nowadays, renewable energy becomes more and more of a problem. Rather, the fossil fuels we use to create energy are the problem, and renewable energy is the solution. We’ve tried wind, solar, water, nuclear, and plant energies as alternatives to gasoline and coal. But, one extremely promising form of energy yet remains: fusion.
     
    We currently use only fission to create energy, which is the process of dividing large molecules by shooting various particles at it. However, this process has many dangers. It creates large amounts of radioactive waste, can lead to meltdowns, and can be used to create milder atomic weapons. Fusion, on the other hand, does none of these things. So, why don’t we use it?
     
    Well in short, we can’t. Fusion takes an enormous amount of heat to create: about 100,000,000 degrees Celsius. The Sun can do it because while it only manages to reach 15,000,000 degrees C, it also has the added benefit of immense amounts of pressure in its core. We currently experiment with using magnetic fields to create pressure and gamma rays to heat materials into plasma, but the most energy we’ve ever gotten out of a single experiment was 16 megawatts. Though it may not be much, we’ve improved greatly, and 25 years ago we thought fusion would be impossible on Earth. With time and money, we may yet learn how to control this miracle energy source.
  10. PaperBoy
    Ever wondered how the Universe will end? Well, if you’re not religious, there’s a myriad of options to choose from.
     
    Lots of people know about the Big Crunch. In short, this theory dictates that at the end of the Universe’s lifespan it will stop expanding and begin to collapse in upon itself, condensing into an infinitely dense singularity. However, soon the outward pressure will trump the inwards force of gravity, and the Universe will explode in one massive supernova and be created again. This cycle of Big Crunches and Big Bangs is thought to have continued on forever, and will do so for all of eternity.
     
    There’s also the Big Rip, which says that the acceleration Dark Energy causes on the Universe’s expansion will be too great for gravity to overcome. This acceleration begin will begin to rip large objects apart like galaxies and solar systems. Eventually, it will tear down smaller and smaller objects into their components until all matter in the universe is the smallest unit of mass in existence.
     
    However, the most plausible scenario is currently the Big Freeze. All things in nature wish to reach a maximum state of entropy, and heat disperses evenly. So, as the universe expands forever, this heat will continue to be spread farther and farther apart. As large objects and even molecules are destroyed, the heat they create will dissipate into the abyss forever. Eventually, all stars will go out, and the Universe will be a frozen wasteland.
     
    Enjoy your time on Earth while it lasts, ‘cause it’s gonna get pretty cold soon!

  11. PaperBoy
    The Sun provides us with a lot of things, most significantly life. However, without one of the special properties of our planet, it would quickly destroy us. This is because the Sun emits “solar wind.” Of course, there’s no atmosphere in space, rather, this term defines charged particles moving at supersonic speeds out of the Sun towards Earth. So, how does Earth protect us from this onslaught?
     
    Well, it actually has a dipole magnetic field surrounding it. This means it acts like a double sided magnet with a North and South pole. This field only provides 25-65 uT, but because most solar wind is comprised of beta or alpha particles and neutrons, it’s more than enough to keep us safe. How is it made? Well, the most common theory is the Dynamo Theory. This belief states that celestial bodies emit magnetic fields due to convection currents in the core of the object, spinning electrically conductive fluids in the mantle for long periods of time. Scientists have even linked plate tectonic movements to the reversing of Earth’s magnetic field, which happens every several 100,000 years or so. These poles similarly account for the usability of compasses.
     
    The magnetosphere - where the field does its work - exists for several kilometers outside the atmosphere, and protects it as well from harmful particles. Thank God too! Our ozone can’t take much more!
  12. PaperBoy
    Nowadays, almost every kid has a computer, whether it's their own or not. And, with that computer, nearly every kid listens to some type of video, music, or even alert messages. Without sound, computers just wouldn't be as useful. But how do computers make sound?
    The answer is quite complicated. Older computers used the common magnetic speaker, which included some array of copper wires and an iron magnet. The original design was a simple iron magnet inside a copper coil, vibrated by the electric field induced inside.
    Nowadays almost all computers use piezoelectric speakers. This type of speaker is named after the piezoelectric effect, which describes the quality of certain materials to create an internal electric charge due to mechanical stress. A voltage is supplied to a resonator or diaphragm, which in turn begins to vibrate as the electricity causes stress in the object, reversing this effect. The sound of the speaker is controlled by a process called pulse-width modulation. This means that the power supplied to the speaker is digital, either 0V or 5V. However, by adjusting the duration of the duty cycle (the amount of time it gets 5V) different sounds can be created.
    Lots of ingenuity went into those tiny little buzzers you listen to every day. So take some time and really enjoy them. Some robot is slaving away making them right now.
     
     
  13. PaperBoy

    Over 9000

    By PaperBoy,

    We all know Einstein's famous equations E=mc^2. It means that energy and mass are two halves of the same variable, and that a little mass makes an enormous amount of energy. We also know its disastrous effects, as evidenced in the US's infamous Manhattan Project.
    The first nuclear bomb ever tested was dubbed "The Gadget, " and the test itself was nicknamed the Trinity Test. It was conducted on the morning of July 16, 1945 in the Alamogordo bombing range of New Mexico. The bomb was said to release the energy of about 20 kilotons of TNT, or about 84 terrajoules. Now, if we plug that number into Einstein's equation, we can find exactly how much radioactive plutonium was put towards the actual explosion. Using 3E8 as c and 84E12 as E, we find that the mass of the plutonium reacting was about 9E-4Kg.
    However, I assure you much more plutonium was used to create the Gadget than that. So where did all the rest go? Well, into the massive amount of heat and light created, more than enough to blind people and incinerate standing structures for miles. This conversion seems to be the most powerful force we can today harness, and it truly has awe inspiriing results.
  14. PaperBoy
    Lots of people have heard of the word "supernova." It's gained a lot of popularity because of its incredible power. It's not surprising, after all, supernovae are the most powerful event in existence believe it or not. They're incredibly rare as well, only three have been observed in the Milky Way in the past thousand years, and that's a lot of space to blow up in.
    You probably already know that a supernova is the death of a star. However, there are two ways this happens. In a binary star system, if a white dwarf begins to suck matter from its neighbor, then it will eventually gain too much mass to contain itself with gravity and will explode. The more commonly known tactic is when a massive star begins to run out of fuel for fusion. Its mass begins to fall into its core, which then collapses in upon itself and explodes. During these eruptions, supernovae can appear anywhere from a dim light in the sky, to a supposedly new star, to a bright light that outshines its entire galaxy to us.
    Supernovae are incredibly important to the formation of the universe as well. All elements heavier than iron had to have been created in a supernova. Not only that, if you believe in the Big Band Theory, that itself was simply a massive supernova, if you'll pardon the repetition. They play a key role in sending various elements across the universe for solar system creation. Supernovae are even part of the reason we know the universe is expanding, and constantly provide evidence with which to study the Big Bang Theory.
    I myself think supernovae are one of the coolest events in the known universe. My dream is to someday meet one, inevitably incinerating in the following explosion.
  15. PaperBoy

    Pushing and Shoving

    By PaperBoy,

    We all know that atoms are comprised of electrons and a nucleus. The nucleus is tiny and dense with positive protons and neutral neutrons, while the electrons orbit far away and are negative. So then, why don't atoms fall through other atoms if there's so much empty space in between? Two reasons really: the electromagnetic repulsion and the Pauli exclusion principle.
    The first is simple. When you bring like charges together they repel, and this force is proportional to the inverse of the distance between the two charges squared. This means that if you bring objects closer and closer together, the resisting force will become greater and greater until it overcomes the force pushing the two objects together.
    The second theory could kill you if you aren't careful, so take breathers in the middle. Quantum mechanics dictates that electrons are in every possibility at once. So, really, there is no empty space between the electrons and the nucleus: it's all filled with possibilities. However, Pauli's exclusion principle also dictates that no two identical fermions (let's just say this includes electrons and move on) may occupy the same quantum state simultaneously. Thus, because both the electrons from one atom and the electrons from another atom cannot exist in the same place, but still fill up their surroundings with possibilities, at a certain point they become incredibly hard to push into each other any further. At this point you have what's called degenerate matter.
    Thus, crushing atoms into each other is almost impossible. The only reason we can pass through liquids and gasses is because we simply push them into the surrounding empty space or around each other.
  16. PaperBoy
    TV's have risen in popularity tremendously since their invention, and despite continuing advancements in communication they continue to be a major project across the world. This relevance is in a large part due to the innovation which has kept them higher quality, easier to operate, and/or more useful than ever.
    TV's started out using cathode ray tube technology to display a picture. In this setup, a vacuum tube rockets electrons towards a phosphorescent screen. Anodes accelerate the electrons before they are deflected by two coils of electrically charged wire, creating an electric field. These deflected electrons strike the screen and glow in different colors due to the intensity with which the tube shoots them out. It scans left to right, top to bottom, until it finally reaches the bottom, and repeats.
    Nowadays, however, TV's work very differently. One style is the liquid crystal display. Lights on the bottom of the TV shine upwards, illuminating the inside of the TV. Two polarizing planes at 90 degree angles to each other block all regular light from reaching the screen. However, between the planes is a section of nematic liquid crystals which are twisted. On each end are glass planes coated with electrons to adjust intensity. As different voltages are applied to these glass panels, they twist and untwist the crystals in order to selectively block light from passing through the polarized plane to the screen. After the polarizing plane are one of three colorizing planes: red, green, or blue. By placing three of these arrangements next to one another, a pixel is created.
    Another style is the plasma display. In plasma displays, there are cells of ions and electrons free flowing, which are each pixels. Each pixel has a different color lens to transform visible light into one of the average three RBG. When an electric charge is sent to the cell, the positive ions and negative electrons both move around and combine with their opposites, creating light which passes through the colored panel and hits the screen.
    Whew! We need to stop making TV's and get back to books! Seriously, when's the last time someone reinvented the book? I want a plasma book.
  17. PaperBoy

    Out with the Old

    By PaperBoy,

    Recently I was playing video games with my brothers and their friends when they decided to move the party to another house. We were all set to go when suddenly someone mentioned the TV involved. This was soon drawn out into a long conversation about why old video games don't work well with new TV's, but work perfectly fine with old ones. Why is that?
    Well, the problem I am mentioning is called input lag, which is the loose definition for any large difference in time between the input to a hardware device and its associated output. For example: hitting a button on a game controller and waiting a second before the TV displays the action. Many of my brothers' friends noted that this input lag was almost never seen with old cathode ray tube TV's, while it can be often seen with liquid crystal display or plasma.
    The reason this occurs is because of the difference between the analog signals of old video game consoles, and the digital signals of new TV's. When an old video game controller is pressed, the controller takes information and packages it in an analog signal to be sent to the TV. The TV then accepts this signal for display. Old TV's used analog display, so they could simply unpack and use the information. However, new TV's use digital systems, and must first demodulate the data (which includes changing the carrier wave) to be unpacked. They also nowadays store video information, which previous TV's did not.
    As a result, your original smash bros. game may not perform as well as you'd like unless you fish something archaic out of a trash heap. Good luck with that buddy.
  18. PaperBoy

    Something Different

    By PaperBoy,

    Once somebody asked me what I felt was more important: art or science. At the time I instinctively replied science, but upon further inspection I think that might have been a bias.
    I know a lot of people who don't want anything to do with science, and would much rather spend time expressing themselves in new and interesting ways. There's nothing wrong with either I suppose, but now that I'm getting older it might be good that I make a judgement call.
    I certainly still believe in stimulating progress as much as possible. But then again, who's to say that art isn't progress. Maybe it's a progress of the mind, the practice of developing new ideas and the cultivation of outside the box thinking. I think we can all agree, no matter who you are, that you need to be inventive to create progress. Isn't that the whole point?
    So then which is more important, cultural or mathematical progress? If you had to choose to keep one and destroy the other, which would you pick?
    I think that for me, the answer is still science. Of course we need free thinkers and inventors in order to really get anywhere in science, but if we focus on free thinking without getting results then what's the point? I don't think moral growth or maturity really mean much if you're not going anywhere anyway. I mean, what's the point of pondering what it means to be human if we'll never go out into the universe and find something that challenges that belief? Maybe I'm still locked into my logical thinking pattern, but I feel like there's a pretty good argument for seeking results over better ways to get results. Then again that goes against all the Disney movies I watched as a kid...
    Tell me what you think if you care, I'd love to get another perspective on why either art or science is necessary to human development.
  19. PaperBoy
    The electromagnetic spectrum is the range of electromagnetic radiation frequencies in the universe, which includes radio waves, x-rays, all kinds of light, gamma rays, etc. The reason the Em spectrum is segregated as such is because of its common interaction with matter. For example: gamma rays tend to create particle, anti-particle pairs when interacting with other matter, infrared rays tend to vibrate molecules in matter. This radiation is known to occur any time charged particles are accelerated, and create both electric and magnetic fields perpendicular to each other, hence the name.
    For a long time scientists believed there was no limit on this range, only a limit on what we could detect. So, is there a limit? Actually, yes.
    Scientists now surmise that the upper limit on the wavelength of EM radiation is the width of the universe itself. The lower limit, however, is a constant called a Planck length.  This is the theoretic smallest length of anything possible in the universe, and is1.61619997 E -35 m.
    Most importantly, this radiation allows scientists to look where visible light could never go. X-rays are frequently used to scan patients for damage, and every scan the universe for new discoveries. We'd be pretty far behind in astronomy without this powerful stuff.
  20. PaperBoy
    Did you know there's actually a shortest possible length in the universe? At least there is supposedly, scientists believe we'll never be able to create any sort of measuring or analyzing device short enough to view it. It's called a Planck length and it equals 1.61619997E-35 m. It's derived from Planck's constant (you know, E=hf), the gravitational constant, and the speed of light.
    One cool way to think about it is this: imagine a .1 mm dot, about the smallest length the naked human eye can see. Now, turn that dot into a universe of its own. Inside that universe, a Planck length would be another .1 mm dot. Pretty cool right? This means that a .1 mm dot is almost exactly half way between the observable universe and a Planck length.
    Some scientists believe that a Planck length is the exact length at which spacetime becomes dominated by the laws of quantum mechanics, and thus any length less than it would be impossible to determine. Others also believe that it's related to the size a black hole enlarges each time it takes in matter.
    Though currently scientists can't really do anything at all with this information, it's still pretty cool to know that there is a rock bottom to feeling small. :'C
  21. PaperBoy
    All physics students ought to know about the photoelectric effect. In fact, heck, all people should know about the photoelectric effect. It's incredibly important to our world.
    Here's a short summary. Scientists discovered that many metals actually release electrons when light is shone upon them. Some thought that this meant that the light was simply accelerating or energizing the electrons until they jumped out of the metal. However, upon further testing and changing of the intensity of the light, this was proven untrue. This is incredibly important because it means that light is actually made up of little particles called photons that are striking the electrons in the metal and knocking them out. This idea forms half of the basis for the wave-particle duality of light which has opened up so many quantum mechanics questions.
    So, we know that. But, do you know how we use this effect today? Let's see!
    Night vision goggles use this technology. Photons hitting the goggles strike a metal screen, emitting electrons which then can be accelerated by an electric field. They are then sent to a phosphorous screen where their increased speed shows up brightly. Thus, weak light and radiation outside the visible spectrum can be enhanced to be used for seeing in the dark. This process is used for photomultipliers, though they don't emit any radiation initially.
    The original video capturing devices used it to dissect images. Light hits the photocathode inside the device, sending electrons which are detected and whittled down to only the desired section of the image, which is then deflected to a display device like a cathode ray tube to be viewed.
    These following aren't uses, but they're still cool! The dust on the moon is actually electrically charged by the sun's light, and levitates above the surface. Spacecrafts facing the sun develop unbalanced charges from its light, which can threaten delicate instruments. Electroscopes can't be used to test for static electricity if exposed to too intense light.
    In the end, the photoelectric effect is a really cool way to transform light data into electrical, which can then be controlled magnetically as well, opening up the possibilities for the study and usage of light. How cool is that!
  22. PaperBoy
    There's been a good deal of hype surrounding gravitational waves recently. It's been all over the news, and has something to do with Einstein as far as we know. Wondering what it all means? Well wonder no more, I'm here to deliver the abridged version of what you need to know! For dummies.
    So, what is a gravitational wave? Well, it's a wave that propagates through space-time itself. Remember how space and time are actually one thing, like a quilt over the universe? Well, gravitational waves travel along that plane, stretching and shrinking space itself. And, it acts upon space-time in perpendicular directions, kind of like an electromagnetic wave. In short, it's a transverse wave (think of a sine wave) that acts in two different directions, the horizontal and the vertical.
    Now, that may still be confusing, so imagine this. You're standing at the end of a long square hallway with lights all along it. A gravitational wave starts at the other end, traveling toward you, and means business. As it approaches you, you would see the walls and ceiling of the hallway bending in and then puffing out rhythmically. As the walls puff out like they're being pushed in the center, the ceiling and floor get sucked in towards the center of the cross sectional hallway like someone pulled in the middle. Then, the two pairs of sides switch, and the ceiling/floor puffs out while the walls get sucked in. It travels closer and closer towards you, pushing and pulling in time, until it reaches you. At this point it crushes your arms into your torso, rips your head and legs off, then switches and stuffs the top and bottom back on like a hastily saved muffin and pulls your fingers off. Rude.
    But, that doesn't mean gravitational waves aren't cool! Check out part two for some more in-depth understanding now that you know what gravitational waves look and feel like!
  23. PaperBoy
    So, now that you know what gravitational waves are, where do they come from? Well, they are generated from some of the most energetic processes in the known universe. This includes supernovas (like the Big Bang), neutron star collisions, Black Hole mergers, etc. In actuality, gravitational waves can occur any time masses accelerate in non-symmetrical motion. However, the only detectible sources are the ones listed above. Even these events are often incredibly difficult to detect, since the waves diminish to near unnoticeable levels by the time they reach Earth (thank goodness too, remember that head and arms thing from the last post? uugh). Though, gravitational waves themselves can actually have amplitudes larger than the universe.
    Gravitational waves were first proposed by Albert Einstein in 1916 as part of his theory of relativity. So, I guess it only took us a century to match his intellect, high five! Anyway, they also refute one of Newton's assertions in the Newtonian theory of gravitation, since Newton postulated that physical interactions propagate at infinite speeds. In reality, gravitational waves only travel at the speed of light, which isn't even as fast as some kids drive to school in the morning. But, what's really interesting about gravitational waves is that they actually tell a lot about the events from which they occurred. For example, the waves first detected were from the merging of two black holes. With multiple interferometers - the instruments used to measure gravitational waves - you can even triangulate the position the waves originated from. Scientists are currently hoping to use information gleaned from the study of gravitational waves in order to gain insight into the Big Bang and the ever elusive dark matter.
    Though, like i mentioned earlier, they're incredibly small by the time they reach Earth. So minute in fact, that Einstein thought that humanity would never be able to measure one. Einstein: 1, U.S.: 1. Thankfully, we have a really cool instrument for measuring them. Check in for part 3 to get the full scoop!
  24. PaperBoy
    So, an interferometer is the instrument used to measure gravitational waves. But, how do they do it?
    Well, the interferometer is an ingenious invention created by Albert Michelson back in the 1880s. The concept is actually quite simple too. The design starts with a concentrated laser beam, like any good invention. Next, the laser beam hits a beam-splitting mirror at a 45 degree angle. Thus, half the beam travels straight through the mirror, and the other half is deflected at a 90 degree angle. Each beam separately travels down several mile long corridors to hit a solid mirror, and bounce directly back. Once the beams again meet up at the beam-splitting mirror they collide in perfectly opposite tandem, crests meet troughs, and the two laser halves destroy each other.
    Wait... so then how does it measure a gravitational wave? Well, don't forget, these waves actually bend space-time. And, they do it cyclically, with one direction stretching while the other shrinks, and then swapping. So, when they meet the interferometer, they actually elongate one of the corridors, while shrinking the other. This shifts the laser out of phase, and the two halves no longer cancel perfectly. Thus, the now undistorted laser recombines in the beam-splitting mirror and continue on to hit a photosensitive device. However, gravitational waves oscillate, so the end result actually comes up as a strobe light. Scientists then take this flashing light in as data with a computer, and transfer it into sound waves to be more easily understood. After all that work, one of the most powerful events in the universe is finally reduced to a small beep. It is exactly this beep which scientists at the Advanced LIGO observatory heard on September 14, 2015 at 5:51 am.
    Now, even more observatories are being put up all over the world in order to gain more accurate readings of these outlandish events. The soonest completed may be a new LIGO in India, and with this new observatory there will certainly be more gravitational wave sightings to come. With any luck, this outstanding discovery will lead to some excellent quantum mechanics and origin of the universe realizations.
  25. PaperBoy
    In my high school physics class, we've been talking a lot about circuits of late. And, in such a discussion who can forget capacitors?
    Most people know that capacitors are usually created by separating to conducting plates by a small dielectric. They store electrical charges and in doing so store electrical energy through a temporary electric field. That's all fine and good, but where is this invention used in the real world and for what purpose?
    Well, one basic use is the storage of energy. Some devices are much easier to use if they can keep charged while their battery is replaced or fixed. Usually this appears when devices need to keep their memory files when no longer connected to a power source. Or, capacitors can be used to make UPS's, or Uninterruptible Power Supplies. These devices maintain voltage to a device when the normal electricity source is obstructed, usually so that nothing is lost or damaged before a backup generator turns on. 
    Capacitors can also be used to smooth out DC currents. This can include signals traveling to audio devices, in which the capacitor resists any extra electrical power. They can even separate AC and DC currents, since AC passes through unchanged while DC current is absorbed to charge the capacitor.
    They are also often used to start up motors. Since starting an electrical motor is always much harder than running one, sometimes capacitors can be used to deliver a kick start. This can often be seen in hair dryers and vacuum cleaners.
    There are plenty of uses for your friendly neighborhood capacitor! Thank Farad they were invented and perfected over the years!
     
    --Notice: do NOT mess with capacitors. Because they release large amounts of charge in small amounts of time they are VERY DANGEROUS. Vacuum cleaners often feature capacitors which are more than large enough to kill a human being. Stay away and respect the power of electricity--

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