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
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
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
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
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
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.
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
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
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
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
This past week it has gotten pretty cold up here in the (somewhat) North. With windchill, temperatures have dropped below zero, and with weather like that it can always be a struggle to stay warm. But with the proper clothing, one can still brave the harsh climate and still have a good time. We might often take it for granted, but how exactly does this insulating process work?
Heat travels in three ways: conduction, convection, and radiation. Conduction is simply the transfer of heat by c
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
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
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
'Twas only yesterday that I took my inaugural ski run, traversing the trails of Bristol, and as I cruised down the mountain I began to reflect on the nature of skiing, particularly waxing. My skis weren't particularly well waxed for the day, so I wasn't going quite to fast, but I did have experience waxing skis beforehand (mostly with nordic skiing - for that it was a weekly affair). When one considers the purpose of wax, it's natural to assume that all it does is make the ski smoother, fillin
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
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
The second-largest moon in our solar system, Titan, orbits around Saturn, about 8.5 AU (the distance from Earth to the Sun) away from us, making it a very chilly place. A fairly massive moon (80% more massive than our moon, according to Wikipedia), it has the unique characteristic of having an atmosphere that obscured views of the surface until the launch of the Cassini-Huygens mission in 2004, designed to chart out primarily the Saturn system.
A moon with an atmosphere is strange, and inter
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
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,
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
Boomerangs to some can be quite mysterious. One may ask, "why do they fly the way they do?" But fear not, for I'm here to explain them to you.
At first glance, a boomerang might appear flat to the unsuspecting eye. But alas, for a boomerang to return to your hand, it must actually act a bit like a helicopter rotor, with one side angled up one way and the other the other way, so that when it spins it creates lift.
But when you think of a helicopter, you think of something going up and dow
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.
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
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
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