Posts Tagged‘video’

Seeing the Invisible, Radiation Peppered World We Live in.

There’s a lot more to the world we live in that what we can see with our eyes. The colours of the world that we see are merely a subset of the wide spectrum of available light, one that extends out in both directions in an infinite expanse of wavelengths. Beyond that there are countless other things happening around us which eyes simply can’t perceive, that is until we construct something that allows us to see the world that’s invisible to us. One such device is called a Cloud Chamber which allows us to see the streams of ionizing radiation that permeate throughout our world. The video below is probably the best example I’ve seen of one and it makes for some extremely soothing viewing:

It’s striking to see the chamber light up constantly with just the background radiation that’s ever present here on earth. Even if you’re familiar with the idea of the  world having a constant source of radioactivity it’s still another thing to see it in action, the ionizing particles whizzing through the space at an incredibly rapid pace. Adding in a radioactive source is a great way to visualize what radioactive decay is and how various materials decay at different rates and in different ways.

Cloud Chambers played an important role in the early days of particle physics with the discovery of the positron (the anti-electron) and the muon. There have been numerous improvements to the devices in the time since they were first used with the modern day equivalents being solid state devices, typically cooled to cryogenic temperatures. Unfortunately the modern versions don’t provide as good of a show as their historic counterparts did but we’re able to do much better science with them than we ever were with a cloud chamber.

Super Cereal.

Looking at the ingredients labels on food can be both an insightful and frightening affair. I’ve long been in a habit of doing it and I always find it fun to research some of the more esoteric ingredients, well that is right up until I find out where some of them come from. It’s the old adage of not finding out how the sausage is made, although in reality you should probably consider that with all things that you put in your body. Still when I watched the following video I was honestly surprised to see the outcome, as I didn’t think the effect of extracting iron from cereal would be so dramatic:

The first half of the video explores the idea that there’s elemental iron within cereal which can then be attracted by a magnet. Whilst this is true to some degree, the iron within the cereal will feel an attraction to a magnet, you can actually perform the exact same experiment with cereal that is bereft of any elemental iron content. This is because water is a diamagnetic material which is a fancy way of saying that in response to a magnetic field it will create its own inverse field in response. For the cereal and magnet experiment this means the water actually divots around the magnetic field which the piece of cereal then falls into. The iron in the cereal helps this process along of course, but it’s not the only force at play here.

However the extraction of the iron from the cereal was pretty astonishing, especially considering just how simple it was to do. Trying to extract other elements from the cereal would prove a much harder endeavour which is why I think an experiment like this is such a powerful visual aid. You’re literally seeing the iron being pulled from the food you eat which, in turn, makes you think about all the other things that are listed on the ingredients label. It might not be a particularly pretty picture that you end up with, but at least you’ll be far more aware.

I wish I knew about these kinds of science experiments when I was a kid!

A Treatise on Battling Global Warming Bollocks.

The war against bullshit is asymmetrical. I couldn’t tell you how many times I’ve had someone stumble across my blog post and rattle off a paragraph or two which then took me 10 times as long to debunk. It’s not so much that I don’t have the evidence, they are always demonstrably wrong, however the amount of time required to provide the proof to debunk them always outweighs the time it takes for them to spout it. Thus whenever I come across something that can aid me and my fellow crusaders against bullshit I feel compelled to share it, in the hopes that one day we can turn the asymmetry over to our side so that, one day, spouting bullshit becomes the harder proposition.

And to that end I share with you the below video:

I’ve come across pretty much every argument in that video before however I’ve often struggled to find an answers that are succinct as his. Of course I’m under no delusions that this video would turn a hardcore denier around, they’re a different breed of stubborn, however it does a great job of highlight the faults in the arguments that many more reasonable people make. His previous videos showed just how scattered the public’s knowledge is on this subject and so this follow video will hopefully go a ways to improving that.

There’s still a long fight ahead to convince the right people that proper action needs to be taken, something which us Australians should hopefully be able to rectify at the next election.

The Science of Popping Joints.

Ever since I can remember my joints have always been prone to popping and cracking. It was the worst when I was a child as I couldn’t really sneak around anywhere without my ankles loudly announcing my presence, thwarting my attempt at whatever shenanigans I was up to. Soon after I discovered the joy of cracking my knuckles and most other joints in my body, much to the chagrin of those around me. However even though I was warned of health effects (which I’m pretty sure is bunk) I never looked up the actual mechanism behind the signature sound and honestly it’s actually quite interesting:

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Interestingly though whilst cavitation in the synovial fluid is one of the better explanations for where the sound originates there’s still some other mechanisms which can cause similar audible effects. Rapid stretching of ligaments can also result in similar noises, usually due to tendons snapping from one position to another. Some sounds are also the result of less benign activities like tearing of intra-articular adhesions tearing, although that usually goes hand in hand with a not-so-minor injury to the joint.

There’s also been a little more investigation into the health effects of cracking your knuckles than what the video alludes to. A recent study of 215 patients in the age range of 50 to 89 showed that, regardless of how long a person had been cracking their knuckles, there was no relationship between cracking and osteoarthritis in those joints. Now this was a retrospective study (in terms of people telling the researchers of how much they cracked their knuckles) so there’s potential for biases to slip in there but they did use radiographs to determine if they had arthritis or not. There’s no studies around other joints however, although I’d wager that the mechanisms, and thus their effects, are very similar throughout the body.

And now if you’ll excuse me I’ll be off to disgust my wife by cracking every joint in my body :)

Print Yourself a House.

Ever since I first saw a 3D printer I wondered how long it’d be before they’d start scaling up in size. Now I’m not talking about incremental size improvements that we see every so often (like with the new Makerbot Z18), no I was wondering when we’d get industrial scale 3D printers that could construct large structures. The steps between your run of the mill desktop 3D printer and something of that magnitude isn’t a simple matter of scaling up the various components as many of the assumptions made at that size simply don’t apply when you get into large scale construction. It seems that day has finally come as Suzhou Yingchuang Science and Trade Development Co has developed a 3D printer capable of creating full size houses:

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Details the makeup of the material used, as well as its structural properties, aren’t currently forthcoming however the company behind them claims that it’s about 5 times as hard as traditional building materials. They’re apparently using a few of these 3D printed buildings as offices for some of their employees so you’d figure they’re somewhat habitable although I’m sure they’re in a much more finished state than the ones shown above. Still for a first generation product they seem pretty good and if the company’s claims hold up then they’d become an attractive way to provide low cost housing to a lot of people.

What I’d really be interested to see is how the cost and materials used compares to that of traditional construction. It’s a well known fact that building new housing is an incredibly inefficient process with a lot of materials wasted in during construction. Methods like this provide a great opportunity to reduce the amount of waste generated as there’s no excess material left over once construction has completed. Further refinement of the process could also ensure that post-construction work, like cabling and wiring, are also done in a much more efficient manner.

I’m interested to see how inventive they can get with this as there’s potentially a world of new housing designs out there to exploited using this new method. That will likely be a long time coming however as not everyone will have access to one of these things to fiddle around with but I’m sure just the possibility of a printer of this magnitude has a few people thinking about it already.

Nitrogen’s Crystalline Formation is Astonishingly Cool.

Liquid nitrogen is a scientific staple that I’m sure we’re pretty much all familiar with. It’s a great demonstration of how the melting and boiling points can vary wildly and, of course, everyone loves shattering a frozen banana or two. However seeing the other stages of elemental gases is typically impossible as getting the required temperature is beyond the reach of most high school science labs. However there is a trick that we can use to, in essence, trick nitrogen into forming a solid: reducing the pressure to a near vacuum. The results of doing so are just incredible with the nitrogen behaving in some really peculiar ways:

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The initial stages of the nitrogen transitioning into a solid is pretty standard with the reduced pressure resulting in the superheated boiling, plunging the temperature of the remaining liquid. The initial freezing is also something many will be familiar with as it closely mimics what happens when water freezes (although lacking water’s peculiar property of expanding when freezing). The sudden, and rather explosive, crystalline formation after that however took me by surprise as I’ve never really seen anything of that nature before. The closest thing I could think of was the fracturing of a Prince Rupert’s Drop although the propagation of the nitrogen crystalline structure seems to be an order of magnitude or two slower than that.

What really got me about this video is that it wasn’t done by a science channel or vlogger, it’s done by a bunch of chefs. Liquid nitrogen has been used in various culinary activities for over a century, mostly due to its extreme low temperatures which form much smaller ice crystals in the food that it chills. It should come as no surprise really as there’s been a huge surge in the science behind cooking with the field of molecular gastronomy taking off in recent decades. It just goes to show that interesting science can be done almost anywhere you care to look and its applications are likely far more wide reaching than you’d first think.

The Eerie Beauty of the Strandbeests.

I remember attending an exhibition about Leonardo Da Vinci a couple years ago and I was astounded by the complexity of some of the machines he created. It wasn’t just that he’d figured out these things where no one else had, more it was some of the things that he designed didn’t seem possible to me, at least with the technology he had available to him at the time. Ever since then I’ve had something of a fascination with mechanical structures, marvelling at creations that seem like they should be impossible. My favourite example of this is Theo Jansen’s Strandbeests, a new form of life that he has been striving to create for the better part of 25 years.

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All of his designs are essentially tensegrity structures (I.E. all parts of the structure are under constant tension) arranged in such a way that when an outside force, in this case the wind at a beach, acts on them they’re able to walk. His initial designs only functioned when the wind was blowing however further designs, many of which you can see in the video, are able to store wind energy and then use it later through some rather clever mechanical engineering. Unfortunately I couldn’t find the best video which has Theo explaining how they work as that one also shows another Strandbeest he created that would avoid walking itself into the ocean (something which I’m still not sure I understand how it works completely).

The idea of creating a new form of life, even if it doesn’t meet the 7 rules for biological life, is a pretty exciting idea and one that’s found an unlikely form of replication: 3D printing. After many people made their own versions of his Strandbeests (I even printed a simple one off, although it broke multiple times during assembly) Theo has made the designs available through Shapeways, essentially giving the Strandbeests a way to procreate. Sure it’s not as elegant as what us biological entities have but the idea does have a cool sci fi bent to it that tickles me in all the right places.

Taken to its logical extreme I guess a Reprap that printed Strandbeests that assembled other Repraps would be the ultimate end goal, although that’s both exciting and horrifying at the same time.

Natural Salt Cubes.

Nature is full of patterns. For the most part these all have an organic feel to them, usually due to the soft curves or seeming randomness that’s inherent in it. Artificial things, like those constructed by man, have the opposite feel to them. Nothing highlights this more than when you compare the view of areas like sand dunes or dense forests against that of a city skyline. However every so often the lines between these two worlds seem to blur together with nature producing something that looks like it was forged by hand rather than by the natural processes of the world. One such example of this, and one I wasn’t aware of until I saw this video, was the creation of salt cubes in the Dead Sea:

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There are many processes by which things like this can occur, Bismuth is a great example of this, taking on shapes that look down right otherworldly in origin, unlike many other minerals that take on much more organic shapes in their natural form. However in the case of Bismuth as well as these salt cubes there’s a simple explanation behind why they end up looking the way they do. For these salt cubes it comes down to the microscopic nature of the molecule, namely sodium chloride (table salt), manifesting itself in macro form.

The Dead Sea is a giant salt lake with an average salt content of around 35%. This is the perfect environment for salt crystals to form and since the solution is so saturated with salt the amount of impurities that make it into the crystal are relatively low. Thus the crystal structure grows in the most idyllic way which just so happens to be a square lattice. Whilst the cubes shown in the video are relatively small the limit on their size is no where near that, with square crystals able to grow up to several kilograms in size. If you were so inclined you could probably grow one several meters in size in a laboratory although the usefulness of such an activity would be highly questionable.

But you would have a giant cube of salt, no one could argue with that :)

Descend Through Titan’s Haze.

Our spacecraft have reached nearly every corner of our solar system, from the barren sun baked world of Mercury to the (soon to be visited) frigid ice ball of Pluto. We’ve gazed at all of them from afar many times but there are precious few we have made even robotic footfall on, with only a single other heavenly body having human footprints on it. Still from those few where we’ve been able to punch through the atmosphere the scenery we’ve been greeted with has been both strangely familiar yet completely alien. Mars is most famous of these but few are aware of the descent video from the Huygens probe that it made on its way down to Titan’s surface:

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Titan gets its thick orange atmosphere from its mostly nitrogen atmosphere being tainted by methane which is thought to be constantly refreshed by cryovolcanoes on its surface. Whilst the mountain ranges and valleys you see were formed in much the same way as they were here on Earth those lakes you see in between them aren’t water, but hydrocarbons. Indeed much of Titan’s surface is covered in what is essentially crude oil although making use of it for future missions would likely be more trouble than its worth.

Still it’s amazing to see worlds that are so like ours in one aspect yet completely foreign in so many other ways. This rare insight into what Titan looks like from on high is not only amazing to see but it has also provided invaluable insight into what Titan’s world actually is. I honestly could watch videos like this for hours as it’s just so mesmerizing to see the surface of worlds other than our own.

The Human Sonic.

I loved Sonic the Hedgehog as a kid mostly because I could simply point myself in a single direction, mash the spin button and then watch as he flitted from one side of the screen to the other at breakneck speed. Whilst the physics of that particular game aren’t rooted in reality some of the principles were namely the forces of momentum, inertia and, most importantly centripetal force. That last one is the force responsible for keeping objects pinned down when going through loop the loops although you usually only see it in action on roller coasters or special stunt vehicles. I honestly didn’t think it’d be possible for a human to accomplish what our speedy blue friend did but it seems that, like many other things, I was wrong.

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I was surprised to learn that the required speed to get around the loop safely was so low, well within the reach of anyone with a modicum of fitness. The real key here though is the technique as the way we humans generate force is vastly different to that of more traditional vehicles that can accomplish this feat. You see the force we generate isn’t in line with the surface we’re on, it’s at something of a 45 degree angle, which means that as you get to the higher parts of the loop you’ll actually be pushing yourself off it with your face heading directly towards the floor.

This becomes evident when you see the initial trial runs where he has to flip himself over at the peak of the loop. In the final, successful run you can see that when his foot hits the peak he doesn’t actually use that to generate any force. Instead he’s doing something like an upside down split kick with one foot travelling from one side of the loop to the other. It’s incredibly impressive to say the least and just goes to show that given enough practice, persistence and good old fashioned science the impossible can be achieved.