Jump to content

oxy126

Members
 View Profile  See their activity

  • Posts

    78

  • Joined

  • Last visited

 Content Type 

Blog Entries posted by oxy126

  1. oxy126

    Magnetic Brakes

    By oxy126,

    Magnetic brakes are pretty cray. With them, you're able to stop stuff from moving WITHOUT EVEN TOUCHING IT. Which really isn't too interesting, but still. It's interesting enough.

    As I already stated, no mechanical contact is required for these to work, which means a significantly smaller amount of wear and tear on the braking system. Because of this and their convenience for certain applications, they're used in things like roller-coasters, or industrial applications, and with design modifications they can be used for regenerative braking in electric automobiles.

    How does it work? Conducting plates typically have a current create in them due to the movement of magnets, as a result of magnetic induction, which according to Lenz's law, will create a magnetic field opposing the rate of change of flux through the surface. This tends to oppose the motion of the magnet, slowing the device down, and when used properly (such as in regenerative braking), the current induced can be harnessed to recharge batteries. It does also oftentimes produce a lot of heat, which can be negative, but sometimes this can be used to your advantage. If you need to heat something (for example, in pipe soldering), creating an "inductance situation" within something like a copper pipe can heat the pipe until it is ready to be soldered. Or burn stuff.
  2. oxy126
    I'm here today to discuss the possibility and implications of time travel...




    ...Just kidding. Time travel isn't real, kids, and you'll just have to get over that. But there is one thing which I think you'll find equally fascinating: PLUMBING.

    Plumbing is pretty insane. Water flowing through pipes and stuff, the transportation of liquids, at times I've found it too much to handle. As many physics students have already learned, Bernoulli's equation and stuff. It all applies to plumbing, and making sure everything flows right.

    Bernoulli's equation is important for things like constricted pipes or transporting water to the tops of tall buildings. For example, when your hose gets kinked, the water through that kink must flow faster in order to maintain the same flow rate, which requires more energy. Using Bernoulli's equation, we can see that this means the flow rate must diminish in order for energy to be conserved, causing the water in your tubing or hose to slow down, which can be a problem especially with a low-pressure water supply. On an entirely different semi-aquatic semi-plumbing topic, the venturi effect, or the effect of a fast moving stream to create low pressure areas, is used in aquariums to bring air into the marine environment while only using a water circulator to do so.

    So yeah. Plumbing.
  3. oxy126

    Science of Sight

    By oxy126,

    For the most part, humans have good sight. A lot of time and effort during our modern era is put into making TV and computer screens at a higher and higher resolution in order to make things look as "real" as possible - that is, to make the pixels onscreen indistinguishable from what we would normally see. But how good are our eyes really? Lets find out.

    Before all of this, I'll direct you to a nice, short, but informative link (https://xkcd.com/1080/), courtesy of xkcd. A good representation of how we see, it outlines the many different parts of vision very nicely. Focusing primarily, however, on the "resolution" of our field of vision, that is, how many "pixels" we can see, we can see it varies. Right in the center few degrees, in the foveal region, we can see stuff quite clearly, which makes sense, because we're looking at it. However, the blurred characteristic of the surrounding areas isn't just because we aren't focused on it, but because there simply isn't as much data provided there - much less, in fact. While our center of vision is comparable to a high-res camera, the surrounding areas are much worse quality, with the entire area outside of the center ~10 degrees containing a fraction of the data that the center area does. Our brain just fills in the gaps.

    So while at times our vision is quite good, other parts could use some work. And even with the high detail of our foveal region, you still might not need that new HDTV. Based on how far away you're sitting, it might not even be noticeable, so don't waste your money.
  4. oxy126
    It's common knowledge that a blue flame is hotter than a red/orange frame. While I'm not entirely sure that is true, having never tested the fact with my own appendages, many reliable sources seem to say it's true. But why, really, is a blue flame hotter? The answer lies with a bit of science on the nature of "light".

    Light with higher frequencies (towards the blue/violet end of the spectrum) contains more energy than light towards the other end of the spectrum, the red/orange end (light in this case refers to all electromagnetic radiation - from gamma to radio waves). And when objects are heated, they radiate energy in the form of light. As you can see in the attached image, this pattern of radiation follows a predictable function dependent upon temperature and wavelength. While certain materials emit certain wavelengths better than others, the general trend is that, the hotter the object the is, the more power it will output at higher and higher frequencies. In other words, a blue flame is emitting more energy at higher frequencies because it is hotter. Theoretically, purple flames would be even hotter, and would most certainly look cooler.

    The big lesson is that there are plenty of ways to quench your curiosity about flammable objects with your eyes, and not your various limbs. Although I guess you can always try.
  5. oxy126
    While it may not be necessarily very physics related, it is an interesting point on the topic of networks, both social and otherwise: the average facebook user is only 4.74 "connections" away from any other average facebook user. The article https://www.facebook.com/notes/facebook-data-team/anatomy-of-facebook/10150388519243859, while from 2011, illustrates the concept that, when the correct pathways are taken, we can all be very closely related. Building on Stanley Milgram's famous experiment trying to assess the validity of "six degrees" of separation between anybody else, this facebook analysis shows how the exponential nature of going from friends to friends of friends puts us all in a strangely close social proximity to one another. In my opinion, it is fairly astounding stuff.

    Networks, internet related or otherwise, are essentially complex structures built from basic components. Whether it is a vast array of *almost* symmetrical distributions of elementary particles giving way over the years to for stars, nebulae, planets, and even life, or just the movement and flow of a bunch of water molecules through your faucet, they are simple yet complicated, where even, as the social network experiment shows, the tiniest part of the system can have an influence on another part completely separate, influences which happen frequently and, as a result, make the prediction of these systems very difficult. Our whole physical world, everything we learn, is based on combinations of the same few elementary particles responding to elementary forces, and things like centripetal force and the laws of thermodynamics are just (often slightly simplified) mathematical models to explain the ways all of these forces and particles interact with each other. So while you can blame the weatherman for getting the forecast wrong, or just wonder why no physics engine to date has implemented a fast yet accurate fluid modelling system, just remember that the world can be a very complex, interconnected place.

Terms of Use

The pages of APlusPhysics.com, Physics in Action podcasts, and other online media at this site are made available as a service to physics students, instructors, and others. Their use is encouraged and is free of charge. Teachers who wish to use materials either in a classroom demonstration format or as part of an interactive activity/lesson are granted permission (and encouraged) to do so. Linking to information on this site is allowed and encouraged, but content from APlusPhysics may not be made available elsewhere on the Internet without the author's written permission.

Copyright Notice

APlusPhysics.com, Silly Beagle Productions and Physics In Action materials are copyright protected and the author restricts their use to online usage through a live internet connection. Any downloading of files to other storage devices (hard drives, web servers, school servers, CDs, etc.) with the exception of Physics In Action podcast episodes is prohibited. The use of images, text and animations in other projects (including non-profit endeavors) is also prohibited. Requests for permission to use such material on other projects may be submitted in writing to info@aplusphysics.com. Licensing of the content of APlusPhysics.com for other uses may be considered in the future.

APlusPhysics Books

APlusPhysics Books

×
×
  • Create New...