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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.

I used to own a half-pipe. Well, a mini-pipe rather. It was a about 1.5 meters tall. Skate baording on it is interesting because at the top of the pipe all you're energy is due to gravity. That means Etop=mgh As one rides down the half-pipe, potential energy is converted to kinetic. At the bottom Ebot=(1/2)mv^2 HOWEVER... In many sports that include a standing on board, a common method to gain speed is to PUMP. Pumping, in its simplest form, is pushing down on the board when you're going up or down a ramp. Or any curve for that matter. Its possible to PUMP on any curve who's concavity faces upwards. In the case of a half-pipe: one can pump on there way down the pipe, thus converting energy in their legs to kinetic energy using an impulse (push). And it works too. Its actually quite crucial while skating on a mini pipe. -Shabba

'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, filling in the tiny holes of the ski so that there is less (dry) friction involved. However, while that is part of what makes a certain type of wax good, a bigger influence is the creation of a thin layer of water underneath the skis caused by contact with the snow. This thin liquid layer allows an even lower coefficient of friction to be achieved, and has to be taken into consideration when waxing your skis (or snowboard). Ideally, only a very thin layer of water is created, because too much will create suction due to the fluid nature of the water, while too little will mean there is still too much dry friction. So the relative propensity of the snow to turn into water on contact has to be taken into account in order to create this balance, and this relative propensity is determined largely by temperature, which is why different conditions require different waxes. Colder temperatures make it harder to create a liquid layer, meaning a stiffer, harder wax is needed, because a harder wax will melt more of the contact layer. On the other hand, warmer temperatures work best with a softer wax. For competitive racers, this means that wax is often reapplied before every race in order to get the optimal conditions. However, for the less enthusiastic, a mid-range wax will often work fine. In case you're every feeling slow on the slopes, take this waxing knowledge into consideration. Soon you'll be zipping around like no one's business.

CHECK THIS OUT It has come to my attention that a man by the name of "A$AP Ferg" has crafted a musical piece of art to help represent who i am and what i stand for. Ferg's song, Shabba, is a wonderful depiction of my everyday life; and for that reason exactly i decided to make a blog post regarding the physics of my dope style. Consider this: Ferg raps that he wears eight gold rings, four gold chains, and one gold tooth in an attempt to be like me. Lets take a closer look as this. Gold, being a fairly dense metal, is not light. Gold rings can weigh anywhere from 3 to 7 Grams (For this example lets say a single ring weighs 4 grams). Gold chains can really be almost any weight you want, but a sensible chain id wear would weigh about 40 grams. Finally, a gold tooth could weigh about 3 grams. Lets do some simple calculations: Gold rings: 4g x 8 = 32g -----> .032 kg Gold chains: 40g x 4 = 160g -----> .16 kg Gold tooth: 3g -----> .006kg All together ferg wears about .198kg of gold as he cops my swag. But lets go a little further: if we take the weight we found above and multiply it by the acceleration due to gravity (10 m/s/s) you'll find that A$AP Ferg is weighed down by a constant net force of about 1.98 Newtons just due to the gold he wears. Heres a list of some foods that weight about the same amount. 2 apples 2 hamburgers 4 sticks of butter 1 large bar of chocolate 4 chicken fingers (Arby's) 2 bagels (Bruegger's) 4 scrambled eggs (McDonalds) Among those, here's some amounts of US currency that also weighs about 2 newtons. 204 dollar bills 100 dimes 40 nickels No one cares about pennys In conclusion, I think it goes without saying that the amount of gold A$AP Ferg wears is impressive. Imagine if you had to carry around 4 scrambled eggs with you all day every day. Not only would that get annoying, but it'd be SUPER messy! I hope you enjoyed this Shabba- Related physics post. If you would like to hear the song that i am referring to in this post (Shabba- A$AP Ferg) you'll have to find that on your own. It can not be posted on this site and shouldn't be viewed by anyone underage due to the explicit nature of language used. I may be Shabba Ranks but i still have class! With love, your friend -Shabba

Hi there. 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 problems using my physics knowledge. I enjoy calculus and I think it will be cool to see some of the applications of what I learn. As a result, I hope to not only hone my calculus knowledge but get some useful information on specific areas of physics and, in general, how to approach difficult, complex problems in an effort to solve them. I always enjoyed electricity and magnetism, and I'm looking forward to that and hopefully being able to dream up some cool uses for my new knowledge. However, no matter what we learn, I think I'll be excited just to know it. So I'm hoping to have fun!

People who know me, tend to know of my "obsession" with shoes. Sure I own a couple pairs (13+?), who doesn't like to buy shoes? Shoes can be a perfect representation of your personality. I take this idea to heart, and have my shoes say for me what I don't need to. But with such a pair of shoes, one must protect them, correct? Recently I ordered a pair of Supra TK Societys, one of my favorite shoes. Now, the black heel cover and Velcro straps are crafted using suede, a light leather with a napped finish. While a lovely material, this material has no reason existing where I live normally, as one minute it can be 70 and sunny and next it's 50 and rainy. Water destroys suede, discoloring it and ridding the material of its trademark napped finish. In order to combat such a problem I utilized Kiwi Waterproofing Spray for Suede products. After treating my shoes and pouring a cup of water on them, I touched them to notice that they were not wet at all. Where does this lead me? Into the actual science of waterproofing finally! (Practicing on old beaters so my new shoes aren't ruined! With waterproofing, practice does make perfect. I generally go with 3 coats, yet you can do as little as 2 or as a much as 5 in my opinion) How does waterproofing work? Well so far, I believe I've come across a reasonable answer. Waterproofing spray is a mixture of chemicals, creating a nonpolar solution that when applied onto the suede, soak into the material and form a bond that prevents (to a degree) the adverse effects of getting suede shoes wet. As a result of spraying the shoe, you should get something like this: (The water just rolls right off, leaving no dark spot or wetness. Magic? Probably. But let's call it PHYSICS.) Thanks to PHYSICS, I can enjoy my current life in a rainy town, while still being able to enjoy stylish clothing using suede. - Credit to Suprafootwear.com for 1st photo, myself for the other 2