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SgtLongcoat

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  1. SgtLongcoat
    For anybody not familiar with Boyle's Flask, it's a reservoir of water connected at the bottom to a tube such that the water infinitely pours into itself. Essentially, perpetual motion. And it's only a theoretical concept.
    With that in mind, watch this quick video:
    https://www.youtube.com/watch?v=OS1KXMsE2qk
    Done? OK, now, can you tell me what the video did wrong?
    If you answered used an obscure method to trick the viewer into thinking it actually worked, you're 100% correct. Based on a few other videos which debunk the scam, fluid dynamics don't work like that, even for a carbonated beverage. When put into an actual constructed Boyle's Flask, without a hidden motor, liquids, even carbonated ones, will eventually reach an equilibrium point where the surfaces of both liquids are at the same height, WITHOUT pouring back into the flask. Even if the liquid is drawn out so that it reaches the end of the tube, instead of flowing down into the flask, the difference in pressure will actually pull the liquid back through the tube until it reaches dynamic equilibrium once again. Of course, this isn't saying perpetual motion is impossible, but it is saying that this specific instance has been largely disproved by actual science.
  2. SgtLongcoat
    Over the weekend, I finally watched Disney's Moana (it's been out for what, almost half a year?), and let me say I thoroughly enjoyed it. It was just the right combination of funny, dramatic, and the Rock singing to keep me in my seat for a solid hour and a half. Now, being Disney, I'm not even going to pretend that physics makes sense (how does the water move like it's alive? is it possible to have a giant air pocket directly underneath water? how is matter conserved when Maoi transforms?), but one part of the film particularly set off my physics sensors, and that was when Maoi was singing about his many accomplishments as a demigod. He stated that he "lassoed the sun," giving the people of Moana's earth longer days, and implying that he pulled the sun closer to the earth. Now, ignoring the fact that the sun is a giant fusion reactor and anything that came into contact with it would almost immediately burn up, I wanted to find out if pulling the sun closer to the earth would actually increase the length of the day.
    Now, in order to make this simple, I'm going to make two assumptions. The first is that Moana's earth follows a geocentric model, that way the sun's movement will actually affect day length instead of year length, and the other is that the sun orbits Moana's earth in a perfect circle. Obviously this isn't true in reality, but it makes the math easier. So, being the sun follows uniform circular motion around the earth, Fc=Fg, meaning mv2/r=GMm/r2, where m is the mass of the sun, and M is the mass of the earth, and r is the distance between them. Simplifying and solving for v, we get v=(GM/r)1/2. Of course, this tells us nothing about the period of revolution. In uniform circular motion, the period T=2πr/v, and substituting in our previous equation, we find that the period of revolution, as a function of the radius (everything else is constant) T=2πr3/2/(GM)1/2. This means that as the radius increases, the period increases, and, more importantly, as the radius decreases, so does the period. Being our period of revolution in a geocentric model is equal to the day length, this means that Maoi pulling the sun closer should have decreased the length of a day, not increased.
  3. SgtLongcoat
    Ever heard a song or some other set of sounds and thought you could make out some sound or phrase that, on close examination, wasn't really there? I'm not talking about misheard lyrics, but lyrics that didn't even exist at a point in a song. Well there's a reason for that. The reason is that, due to the way the song is layered, a specific set of frequencies that the song's instruments play is close enough to the set of frequencies that would be heard if a human were talking, that the brain can perceive it as such.
    Don't believe me? Here's a video of various songs broken up into sets of notes based on the frequencies in their audio files, and then played solely on a virtual piano. There is no other instrument being played here, simply a piano. See how much if it you can make out:
    No, the video doesn't just consist of All Star, but it is a common enough song that you should be able to pick out at least some of the lyrics. So, why exactly does this work?
    As a human speaks, the frequency of their voice changes in order to create the sounds of various sets of letters. At the same time, their voice cuts in and out, also to get the proper sounds of the syllables being said, to make it more smooth. By copying these frequencies precisely at the precise times they occur, it's possible to use any instrument in order to simulate human speech patterns, thus creating the illusion of a voice being heard.
    This not enough to convince you that a computer could mimic a human voice? Look up a video of a neural network analyzing human speech. It can actually get pretty freaky to listen to.
  4. SgtLongcoat
    I recently found an online play-through of a game called OneShot, a fourth wall breaking game in which the main character, Niko, has to restore the sun (just a giant lightbulb) to a world in which the previous sun died out with the help of the player, who acts as a... far from omniscient god of the world that can't directly interact with anything and can only be heard by Niko. Throughout the game, characters reference a material called phosphor, which they say gives off the power of their previous sun, and is used to provide light, generate power, and grow plants.
    While bored, I decided to do a quick google search for phosphor, and it turns out it's actually a real thing, although it doesn't function as it does in the game. In real life, phosphor is a luminescent material used to coat various lights in order to change the color that they emit, with the simplest example being LEDs. For example, most white LED lights actually utilize a blue light to generate their light. How does the light become white then? The answer is that there's a phosphor coating around the light which absorbs light at the blue wavelength, and re-emits light at longer wavelengths, resulting in a full spectrum of visible light instead of a single color. And it should be noted that phosphor isn't a single compound, however, but an entire category of compounds. By changing which compound is used, as well as its density, its possible to achieve a variety of affects from simple lighting to creation of glow-in-the dark materials.
  5. SgtLongcoat
    This Thursday, the Irondequoit High School Philharmonic Orchestra and Choirs will be performing their major works concert at the St. Mary's Church, right next to the Geva theater. It's quite the interesting concert to perform, in that we're all playing in an unfamiliar venue, and have had only a single day where we ALL got together to practice. Oh, and it doesn't help that the acoustics in the church are terrible, arguably only a little better than the IHS gymnasium.
    Why are they terrible, you ask? Let me tell you. In a real theater or concert hall, the entire venue is designed with the acoustics in mind. For simplicity's sake, imagine sound waves as transverse instead of longitudinal. As Physics 1 taught us, if there's more than one source of sound, the sound will be amplified where peak meets peak and trough meets trough, and nullified where trough meets peak. Because the architects who designed the building know, in general, where the performers will be, they'll have a good idea of where the sound will be loudest (likes meet), and quietest (opposites meet), and will thus place the aisles at quiet points and the seats in louder areas, to maximize the enjoy-ability of the performance. Churches, however, (like St. Mary's) are not designed with acoustics in mind. Churches are designed for masses in which they generally have only a single person speaking, meaning that even if sound reflects off the walls, there's generally going to be a pretty similar listening experience everywhere. As such, the seats are organized in straight rows which are evenly spaced, meaning that when the orchestra starts playing, there's going to be some odd spots in which the sound dwindles more. Add to that the cramped feel of squeezing an ~20 person orchestra and ~50 person choir onto and in front of an altar, and it makes for a really interesting performance.

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