Why do bicycles stay " up"? Physics, that's why. Bicycles rely on the concepts of angular momentum and precession to prevent tipping over when. When a wheel is spinning fast, it tends to resist changes in it's angular momentum. This is called 'precession', and is an important concept in bicycles and unicycles alike. When gravity tries to tilt a wheel, it is effectively trying to alter the angular momentum of the wheel. In reaction, the wheel will turn only slightly, and gain a slight 'wobbl
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 experimen
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 plu
A lot of games let you fly planes, but when was the last time one let you fly a rocket? While if that has been what you've been looking for in your time-wasting pursuits, wait no longer, for Kerbal Space Program lets you do just that. As the director/god of the aptly named Kerbal Space Program, you have the ability to launch probes, satellites, landers, space planes, and a whole plethora of fancy little stuff. But behind all of this glamour comes (simplified) rocket science. Much like real r
The gravitational two-body problem is a popular concept in the study of planetary bodies. In essence, it models the paths taken by two massive objects orbiting around each other. Earlier today, I was thinking about our Earth's orbit around the sun, and how while it is easy to think that the Earth doesn't move the sun, it does. So while our solar system surely doesn't have only two bodies, I decided to assume it did (and with a perfectly circular orbit), and calculate just what the orbital rad
One of the "hot" news stories over the past few months has been discussion of the growing impotency of antibiotic treatments for disease and infection. Due to widespread use of antibiotics over (primarily) the last century, antibiotic-resistant bacterial strains have started to emerge, making hospitals more and more dangerous, filled with diseases that are harder and harder to treat.
What this represents is a very serious problem. A large part of modern medicine succeeds due to the prevalen
This week has not been the best week for driving. It's been very snowy, and so cold that road salt has been working very poorly, making the roads a slippery mess. Loss of traction can cause serious accidents, so it is best to drive slowly. In the end, it all comes down to friction. Whether you're fishtailing, or stuck in a rut, or have gone into a full on skid, too little friction can cause serious problems.
Most commonly people will end up fishtailing more in snowy weather, usually while goi
During webassign time I tend to let my mind wander, though it often doesn't wander too far. So I chanced upon the effect Earth's magnetic field has on spacecraft, and the properties a coil of wire in space will have with the aim of spacecraft orientation while in orbit. Digging a bit further, I learned that these devices are called magnetorquers, and so I decided to write about spacecraft orientation and attitude control, both from magnetorquers or reaction wheels or gravity or whatnot.
Below the atmosphere, we have a little problem called global warming, or just in general high levels of pollution for you non-believers, which is the general degradation of our atmosphere and lakes and oceans due to excessive amounts of waste, brought on by agregious practices and poor waste management. In space, there's Kessler syndrome, the hypothetical scenario where, when the amount of space debris orbiting our planet becomes over-saturated, various "leftovers" from spacecraft will collide
I'm a big fan of sound. Music for me is a nice blend of science and art, and I take strides to better my understanding of it occasionally. And occasionally, I enjoy listening to chiptune songs - 8-bit music, as you may call it. A typical sound wave is sinusoidal, meaning it looks like a sine/cosine curve. This is the natural state of a pressure fluctuation that is sound. However, sound waves are (obviously) not all sine waves. Because of the constructive/destructive interference of waves,
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 representat
Recently I came across this article ---> http://www.popsci.com/article/technology/rise-insect-drones <---, detailing the success of engineers/researchers to mimic insect flight, for potential application in insect drones. In short, the article details how the flight of insects was previously misunderstood - based on our conventional notions of flight they were unable to generate the lift to stay aloft - and now, with better study into concepts into "wake absorption" and other fancy flying
I attend the local Rochester parkour gym (http://www.rochesterparkour.com/) on a weekly basis. I also tend to struggle to come up with topics for my physics blog posts. But today, I had a revelation: why not combine the two. So I introduce my new series, the physics of parkour. First up is the "top-out".
A top-out is essentially a way to go from a hanging position on a ledge (a "cat"), to having your upper body above the ledge with your palms supporting you, without clambering up with your el
The trebuchet is an old art. Last time it was seriously used, people were assaulting castles and pillaging the countryside (for the most part). But oddly enough, for a time period associated with such little scientific innovation, is the trebuchet really so complex? It isn't hard to think why it works: it pulls a sling, that sling releases, and so away it flies. But for accurate predictions and optimization, it is actually a fairly complex beast.
You may expect me to explain how it works.
Sometimes I like to sit back and pump some jams. Before the invention of all this modern technology such as speakers and cds and digital audio, such things just weren't possible. Music had to be performed. But with the invention of electrical speakers that all changing. People were able to finally jam out.
The common speaker relies on the principles of electromagnetism. In the center is a magnet (attached to a speaker cone), surrounded by a coil. As the current through the coil fluctuates, the
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 mod
From the beginning of time, this world has been governed by the laws of physics. Which makes sense, because the laws of physics were created to model the patterns of our world. Its actually fairly tautological. But despite this obvious comparisons, it remains an important topic of study, because at its core it is a continuing quest for understanding of the natural world, and it allows us to do great things with that knowledge. While most of my blog posts describe physics, because I wanted to
If a random star were to appear in our skies, and you asked an astronomer how far away it was, they couldn't give you an immediate answer. One thing I always took for granted was how these scientists were able to map the night sky, give us a detailed perspective on what was out there in the final frontier. Some of these methods (like how to determine how far away a star is) can be somewhat interesting.
Using the right math, many people could triangulate the position of an object, as long th
I'm a new Physics AP-C student, and I would like to tell you a little bit about myself. I'm an avid programmer/science enthusiast, and am looking towards entering a scientific or science-related field. I (as one may assume) like science and math, and more leisurely things like playing video games or disc golfing. Things of the sort.
The reason I'm taking Physics AP-C this year is because I'm interested in learning more about physics and I want to solve more challenging problem
Water is strange. Unlike most compounds, its solid form is (normally) less dense, and of a larger volume than its liquid form. Because of this, its very difficult to compress water, because normally there isn't really anything to compress it into. But the story of ice is a bit different from the snow and hail we see falling outside of our windows during these winter months. In fact, ice has many different forms, depending on the conditions it forms in.
The ice we commonly know is called I
Escape velocity, at the surface of the earth, is just about a whopping 11.2 km/s. This means that, to completely escape the force of earth's gravity, from the surface of the earth with the only outside for being gravity, you would need to be going this speed to escape (ignoring, of course, drag - drag forces at those speeds would rip a spaceship apart). So on my way to physics last friday I thought about how to reach those speeds, without the use of costly rocket fuel. One (although initially
In the past few years, the Dyson Air Multiplier has revolutionized the field of recreational air transportation. It's for this reason that I feel it warrants a blog post, all to itself. Lauded for a lack of (visible) fan blades, it is safer than the more common axial-style fan.
The Man Behind the Magic
But how is this trickery pulled off? Allow me to explain.
The Dyson Air Multiplier does, in fact, have typical fan blades. But instead of being open to the air, they are hidden
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 i
High-speed trains have always been a fascinating concept. While they have achieved high popularity in other corners of the world (primarily Japan), they have been mostly absent from American travel. We continue to rely on trains, automobiles, and other forms of public transport, which, while quite fast, are not always the most efficient. Planes in particular use a lot of fuel, and are very costly to travel on (which is, in part, just due to the monopolistic tendencies of airlines). The hyper
There's been a lot of news this past year surrounding NSA surveillance of personal communications. While I'm not here to debate the politics involved with that issue, I am here to describe how they do (part) of it, that way you can do your own surveillance if you really wanted to.
With copper cabling, one of the flaws with using it for communications is the fact that it produces a magnetic field, essentially broadcasting the data within the wire to anyone within short range. Through the hal
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.
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 firstname.lastname@example.org. Licensing of the content of APlusPhysics.com for other uses may be considered in the future.