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jfrachioni last won the day on April 18 2013

jfrachioni had the most liked content!

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About jfrachioni

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  • Birthday 01/16/1995
  1. jfrachioni

    the end

    i thought because i started my bloggery with a prediction and outlook of the course, that i should end it all with an analysis of the year. my thoughts on Mr. Fullerton as a teacher are that he is great at explaining things, and teaching in general. the course is very difficult, and he makes it easier to handle. i also think independent units are a good thing, and that they should be continued. as for blogs, i definitely think writing can help cement understanding of physics concepts, however my opinion is that there are less painful ways of doing so than writing blogs. although I only took ha
  2. have you ever tried forging currency? i know i have. turns out, its not as easy as it looks. paper money has many copy-resistant properties that people can use to distinguish real from fake money. one example of this is the ink used to print a portion of the bill. this ink is special because it changes color depending on the angle it is looked at. this is achieved by infusing the ink with microscopic prisms that have sides that reflect different wavelengths of light. they also have strips of paper inside of them with ink that glows under ultraviolet light. like the highlighters i discussed in
  3. have you ever wondered how your refrigerator gets things cold? i have. turns out, refrigerators use the same physics to cool things as air conditioners, dehumidifiers, and many other household devices. what happens is there is a compressor, two coils of tubing, and an aperture; all working together to make your beverages so damn frosty. if you listen to a refrigerator, what you probably hear is the compressor. the compressor uses electricity to create pressure in the external coil, letting it expel energy as heat, then the gas flows through the aperture and expands, soaking up the same amount
  4. I just read the blog post about the Faraday cage shoplifter, and felt inspired to talk about another use for faraday cages. in todays modern society, mostly everything is electronically operated. since a few years ago, this electronic wave has grown to include credit cards. some companies today put electronic tags in their cards so that one need only to swipe their purse or wallet in front of a sensor to pay for items at stores. unfortunately, hackers have managed to create a handheld device that reads the card information, such as name of person, their address, and credit card number, much in
  5. i don't know if its a law, but as a kid I've always been told to walk on the right side of the road. whether we have adopted this because someone decided that people should have a dedicated side of the road to walk on, or for some other social reason, im here to tell you why its a good idea from a physics standpoint. at least here in america, where the cars drive on the right side as well, physics says that people are safer when they walk on the right. it all has to do with relative velocities. when cars and people are going in the same direction, the velocity of the car relative to the person
  6. highlighters can be useful in many situations, and when you highlight something, it is pretty surprising how bright they look. the other day i was wondering this exact thought, so i decided to look it up. when you see a color, the amount of light entering your eyes is usually the same as the amount of visible light of those frequencies the color reflects at you, however, with highlighter ink, this isn't the case. when you highlight something, apparently the color you see actually creates its own light. visible light, that is. As i found, highlighter ink contains an ingredient that takes invisi
  7. I made the transition from regular to electric toothbrush a month or two ago, and aside from the noticeable improvement in my oral hygiene, I've been thinking about how the toothbrush charges. I understand the manufacturers motivation for not using exposed electrical contacts, as such a design may let water inside, however i found the alternative to be far more puzzling. when you want to charge it, conveniently, you only have to place it on the peg protruding from the base plugged into the wall. With a design including no electrical contact between base and brush, i was confused as to how ener
  8. as i was browsing youtube the other day, i came across this video of a kid who had the unique talent of being able to throw a business card with extreme speed and precision. as i sat in awe of his skills, i began to ponder the mechanisms by which he is able to throw such a flimsy object at such high speeds. when the movie plays through a slow motion section, i am able to have a look at the nature of the cards trajectory. I think the reason he can perform this cool task is because he throws the card with a flick of his wrist, imparting a spin on the card as it is propelled forward. like a bulle
  9. recently, ive been interested in space exploration. not so much exploring stuff, but specifically life aboard the international space station. As one can imagine, everyday tasks we think little about on earth can be pretty complicated without gravity. on earth, we dont have much expirience with surface tension because gravity tends to have far more of an affect on liquids. In space, however, the absence of gravity results in surface tension being much more noticeable, and extremely useful. because the space station is filled with equiptment that is expensive and necissary, yet vulnerable to wa
  10. a few days ago, i put a plastic water bottle in the freezer, hoping that it would cool more rapidly than if i had put it in the fridge. accidentally, i ended up forgetting about it, and a few hours later when i opened the freezer, i witnessed an intriguing phenomenon. when i opened the fridge, i expected the water to be completely frozen, however to my surprise, it was still liquid. after taking the bottle out and placing it on the counter, something else completely unexpected happened; the water immediately began crystallizing. my mind was blown as i saw the wave of ice overcome that which wa
  11. yesterday i opened the window in my room because it was particularly warm outside, and throughout the day as i entered and left my room, i would accidently slam my door, even though i was accelerating it to the same speed to close it as i usually do. as i got used to my now much easier to close door, i thought about possible explainations for this annoying phenomenon. i hypothesized that the culprit was my open window. i figured that when the window was closed, the shutting of my door was harder because while shutting, i was doing work not only on the door, but also on the gasses inside my roo
  12. ill admit its a bit far to reach for a blog post. also it doesnt make too much sense without seeing the movie, which i dont reccomend.
  13. usually, when shot at, the average person would have neither the reaction time, nor the hair strength to deflect a bullet with a braid of his hair. the mere thought of such an impulse delivered to a bullet without crushing it or harming the hair seems to go against all physics, however for those of you who have seen the movie pootie tang, starring pootie tang, you know that pootie dont need no words, pootie dont need no music, and apparently pootie dont need no physics. https://www.youtube.com/watch?v=9F8ahCk_qhY
  14. last year with Mr. Powlin we made some simple water bottle rockets after the ap exam. as we designed and built, we had a basic understading of what our rockets were supposed to look like, but for the most part were in the dark as far as the technical physics behind it. this is what i hope to explain. the common expression "this isnt rocket science" may have you expecting long equations with foreign symbols, however simple rocketry in its essence is counterintuitively pretty simple. for the type of rockets we made last year, only one condition is required for it to maintain its orientation, bei
  15. jfrachioni


    if you were to ask an average physics student about graphene, he would probably tell you about its potential to be used for its structural properties, more specifically its unsurpassed strength to thickness ratio. However, graphene also has many unique and desireable electrical traits. Because graphene is extremely thin, relatively strong, and conductive, you can use sheets of it as plates for a capacitor. the advantageous thing about a graphene capacitor is that you can fit a lot of plate surface area into a small space, giving the capacitor a much higher energy density than conventional batt
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