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  1. Last weekend I crossed the border into Toronto, Canada for a "girls weekend" with my mom and sister. Our main purpose of going there was for a yoga convention for all the yogies of the world. While at this convention, we of course experienced tons of physics! When doing different yoga poses, we experienced the great phenomenon-gravity- at work. When "ohming" or saying "namaste" we experienced sound waves, and the vibration they produced so that we could here them. But when we weren't doing yoga, we somehow still experienced physics! By dropping tons of money at the 3-story mall, The Eaton Centre, we experienced the force that our heavy shopping bags created on our arms. When taking the elevator to a new floor of designer stores, we experienced physics there and how we felt heavier when going up, but lighter when going down due to acceleration. We lastly saw physics when we hit the pool/hot tub in our wonderful hotel. The jets pushed water out creating different waves or bubbles. We also created waves by jumping into the pool. Depending on the type of jump or how hard it was, the amplitude changed all the while carrying the energy we put forth by jumping in. This weekend adventure was full of physics just like everything else!
    3 points
  2. I played dodgeball too!
    2 points
  3. The reason why you get shocked more in the winter is because everyone has their heaters on which draws the moisture out of the air which causes the charges to build up and cling to us more since there is less moisture in the air.
    2 points
  4. ...(But probably not.) In light of the holiday season, I bring to you a Christmas-themed blog post, with a pinch of love and some hints of gravitation. I came home from school today and stepped into the living room, astutely noticing that the Christmas tree had fallen. Obviously, the first thing that ran through my mind was that gravity did this. I mean, gravity's everywhere - it's a pretty likely culprit. You may or may not notice the lamp just above where the tree fell, but I believe it to be of great importance in this investigation. I have deduced that, at any time from 10:00 AM to 2:00 PM on Tuesday, December 16, the gravitational attraction between the tree and lamp created a gravitational orbit that forced the tree out of its holder, and onto the cold ground. Let's take a look. First off, the tree had to begin in static equilibrium - it was still at first. Due to Newton's first law, an outside force had to act upon this tree, and I do believe that the placement of the lamp near this tree provided an IMMENSE GRAVITATIONAL FORCE. So let's dive in. We know that the magnitude of this force is given by GMm/r^2, where G is a constant, M is the tree, m is the lamp, and r is the distance between the two. G = 6.67E-11 Nm^2/kg^2, we know this. The average mass in kilograms for a Christmas tree is about 70 pounds at this height of tree, or 31.75 kg. The mass of the lamp is about 8 pounds, or 3.63 kg. I can already see this force is about to be massive. And the distance between the center of mass of the tree and lamp? About 5.5 feet, or 1.68 meters. Time to calculate. F = [(6.67E-11 Nm^2/kg^2)(31.75 kg)(3.63kg)]/((1.68m)^2) Therefore, the force due to gravity is a whopping 2.72 NANONEWTONS. This incredibly large force undoubtedly caused the displacement of the tree; therefore, gravity ruined Christmas. You may be subconsciously pointing out the holes in my story, like how did a gravitational orbit just occur if the lamp was there the whole time, or perhaps just pointing out the fact that two objects on Earth will likely only apply negligible forces to each other. Fair enough, but keep in mind that there is absolutely no other worldly explanation for this phenomenon. So it's either gravity, or ghosts. You decide. Or maybe the cat just knocked it over.
    2 points
  5. Physics is involved in pretty much everything in life. Throughout my school day I experience all kinds of physics. First period I have Italian where I sit down (along with the rest of my classes) and I am applying a force to the chair and the chair is applying a force to me because of Newtons third law. Second period when I get my math test score back I hit my head against the desk which is also applying a force to the desk and the desk applies one right back. Third period is art class where I gravity is pushing my eyelids down while I struggle to stay awake. Fourth period is APUSH which could be compared to a black hole. Black holes have tons to do with physics. A black hole is a point in space with so much gravity that not even light can escape and that is most definitely APUSH... Fifth and 6th periods are the best of the day because I do not have classes these periods so I can do my homework. Seventh period is English where I push down on my pencil and it leaves a mark on the many papers I have to write. Gravity also pushes down on that pencil. Eighth period could be the first period of a double for physics or if I am lucky its gym. In gym there is so much physics. A ball is thrown and is a projectile motion. Gravity acts on the ball at all times. If were running in gym we push down on the ground with our legs and the ground pushes us back allowing us to run. And then ninth period, well there is too much physics in a physics class to list. Tons of gravity throughout the day and tons of newtons laws. Crazy..
    2 points
  6. So if you haven't heard, a rocket that was supposed to bring supplies to the International Space Station (ISS) exploded on October 28. Here's a short article and video talking about it: http://www.wired.com/2014/10/antares-rocket-explosion/. Obviously, this kind of sucks. The rocket cost about $200 million and now most of the supplies won't make it to the ISS. However, explosions are still really fun to watch, especially one that big and I don't feel bad saying that since the rocket was unmanned. Also interesting is that the rocket was made by Orbital Science, under contract of NASA. This shows that the space industry is slowly because more of a private industry with Orbital Science and SpaceX leading the way at the moment. They aren't sure exactly what caused the rocket to fail, but the actual explosion was caused by the self-destruct being purposefully activated. The real problem was right when it fired its first stage - you can kind of see this in the video. As soon as this problem was noticed, it was decided to destroy the rocket before it reached a populated area and could potentially cause damage. Any number of factors can mess up a rocket launch; there are a lot of variables. Wind speed and direction, an area clear of people, weather, calculations, etc. I think the biggest things I learned from this are that those errors we usually don't account for in our physics labs (FRICTION!!) matter a lot in the real world, and that we still have not perfected going to space. I'm excited for space tourism anyway.
    2 points
  7. So are you saying that in one of these dimensions you're actually good at super Mario??. Fascinating stuff Jake, and don't go putting your cats in radioactive boxes, alright big guy?
    2 points
  8. Hello, my name is Max and I'm a senior in high school. Since everyone else is talking about the sports they play...I will too. My mother often asks me to stop playing tennis because it is such a physical sport, but I rarely listen to her so I continue to play at a varsity level. I can't have any pets except a boring fish because my dad is allergic to the fur on cats and dogs. At the moment I work at a restaurant called Hose 22 and I usually prepare food. I'm taking physics because it was recommended to me by my counselor. But I am excited to start physics because it looks like its going to be very different from all the other science classes. I also really want to learn more about the different forces that can act on objects.
    2 points
  9. Jelliott, I can really relate to your analogies. I too wish to become a beautiful butterfly, to grow and grow until I burst with knowledge. although I find some of your post humorous as intended, I think you struck on very important ideas. I think hard problems can be torture but on the other hand, that makes them that much more rewarding when completed.
    2 points
  10. If you wanted to, you can change your name and remove your last name in the settings! Enjoy physics!!
    2 points
  11. Maybe I'll write a post just about cows...*suspense*
    2 points
  12. Sweet blog post. If you wouldn't mind spreading the love and also buying your two student teachers silver Porsches, we wouldn't complain
    2 points
  13. Soooo, because this is my last blog post for this year ( ), I thought it would be fitting to do a course reflection on the AP-C physics class this year. I thought I'd do it in a "bests-vs-worsts" top 5 format, kind of like you could find on collegeprowler.com when viewing different schools. Top 5 Bests: 5.) Blog Posting [i thought this was really fun! I've never done anything like this before for a class. It brought up interesting physics applications and I thought it was fun to converse with classmates on the site ] 4.) Independent Units [As uncomfortable as I was at first, independent units forced me to manage my time, work harder than usual to learn the topic, and was great preparation for college. I feel like everyone sould experience this kind of a unit before graduating] 3.) Assigned practice problems from the readings [Assigned problems were REALLY helpful. I would've struggled a lot more than I did had I skipped doing the sample problems] 2.) Units with Lecture & book follow-up [This is my favorite way to learn things! The read-then-lecture method] 1.) VIDEOS <3 [Hands down the most helpful resource in Physics] Top 5 Worsts: ...I think this is my biggest beef. I really don't have 5 things to complain about. 1.) Readings weren't assigned [When life gets busy in the middle of the year, especially with a number of APs, sports, etc., readings are the first thing to get cut out for me if they're not assigned. Confession: when the going got tough, I would often skim or not read. I reccomend assigning readings in the future. Kids will complain, but they'll thank you when they see better grades and their AP score.] Overall, this was a successful year. A note to future students: This is by far the hardest AP course I've taken throughout high school. If you want to succeed, you must: A.) Read the textbook and do some practice problems B.) WATCH THE VIDEOS. Whether you're confused or simply want review, these are soooo outrageously helpful. It's like being in class a second time, except in 15 minutes or less instead of 42. Plus, you can skip over any sections that you feel you know solid. C.) REVIEW THE EQUATIONS AND FREE RESPONSE BEFORE THE AP. I went through most of the E&M free response questions as well as both E&M and mechanics equations before the exam. KNOW THE EQUATIONS! I swear equations and key concepts are the majority of the test when it comes to the multiple choice Qs. Any favorite parts of the year? Things you wanted to change? Post below with your opinion! ...I can't believe we only have 1 more day of physics
    2 points
  14. PCX is a workout area that I participate at weekly with my volleyball team. We go on tuesday nights to exercise as a team. I realized while watching videos that i recorded of the exercise's how much physics was applied into each activity. The vertamax that we use for jump training is full of physics. When you use the vertamax you put on a belt with two clips on either side of your hips. You then stand ontop of the vertamax (a square flat surface) and then attach the clips to different color resistance bands. With the vertamax at PCX you can either choose to use it for jump training or leg strength by making the bands go parallel to the floor instead of perpendicular. Once cliped into the machine we are told to jump and go for maximun height. The force of the resistance bands pulls us toward the ground and makes us work harder to get higher into the air. Once we are done useing the clips we unclip the bands and then jump without resistance and analyze the height difference. The jacobs ladder is another machine that we utalize on a weekly basis. Similar to the vertamax you belt yourself into this machine and then "climb the ladder." You can control the speed of the machine with how much force you put into it. If you are working hard and pushing yourself and the machine then the output on the machine will mirror your work and move faster to challenge you. The machine is inclined at a angle so as to simulate climbing up a ladder type object The angle that it is inclined to makes it more difficult to climb. The Pull up bar is also full of physics. With three reps of eight pull ups my team is challenged to bring their entire bodies up into the air transitioning from potential energy into kinetic. We are given band to put our feet into for extra support. The rubberband like bands expand and retract to help differ our weight. The sled is yet another item that we use to work out. Notice this is not your typical snow sled. This sled is a black device that you put weights on inorder to work your legs and arms. Having the sled on the turf surface creates more surface tention and therefore more work to be done by my teamates. There are two different holds that we can choose from when using the sled. The two different holds are all about angles. The higher of the two is easier because you are able to use the machine against itself to push it across the turf. The lower of the holds means that the players body is parallel to the ground and very close to it. The force that it takes to push your legs and arms together to get the seld across the turf is increased from the higher angle hold. Basically every tuesday i have extra amounts of physics added to my day!
    2 points
  15. My childhood, like many others, was spent watching many Disney Movies. One of my all time favorites was the Lion King- I never grew tired of it. One scene that always sticks in my mind is that once music number of young Simba and Nala and, of course, the scene of Mufasa's Death. (0:49-1:20) It can usually bring tears to even the toughest of teens, yes? As a child, this scene really never bothered me and, now, this sad scene seems to bother me so much more. Mufasa died a heroic, and untimedly, death by saving his only son. However, we should move onto the Physics now. How accurate is Mufasa's death, exactly? Could a fall from that height really kill an adult male lion? How far did he fall, anyway? It's very hard to tell but, after reviewing this scene many times I feel I can give a good shot at answering these questions. From what I can tell, Mufasa's fall lasted roughly 5 seconds (1:07-1:12ish), and started from rest before... Scar decided to be a jerk and condemn Mufasa to death. So, using the equation d=vit+(1/2)at2, knowing his falling time was 5 seconds, he started from rest, and acceleration due to gravity is 9.81m/s2; It can be estimated that Simba's father fell about 123 meters. While he seemes to be fairly high before he fell, I highly doubt that the the distance (vaguely seen at 0:50) was taller than the Statue of Liberty. Obviously, it makes sense why a Disney movie would over exaggerate the death of a character, and not care about making the Physics of a children's movie accurate. While real Lions are tough and resiliant, a fall like Mufasa's (even if less than 123meters) would still kill or severely injure an adult lion- not taking into account the stampeeding wildebeasts trampling. So, as expected, Disney's The Lion King takes little care in being realistic... It was still interesting to think about, however! And imagine how cool (at least, I think so) it would be if a childhood classic was actually completely accurate- in a physics sense (because animal's can't talk).
    2 points
  16. Thrilled to help, and welcome to the APlusPhtsics Community! The short version... The College Board says you need to know how to derive them. Very rarely have they asked students to do so, but it has happened... This guide sheet may help with studying: http://aplusphysics.com/courses/ap-c/tutorials/APC-Dynamics.pdf Good luck!
    2 points
  17. I have a very large interest in bees, so for my first blog post I've decided to research how bees see colors differently compared to humans. Through my research I have discovered that the color spectrum of bees is shifted when compared to the color spectrum of humans. Visible light is part of a larger spectrum of energy. Bees can see ultraviolet – a color humans can only imagine – at the short-wavelength end of the spectrum. So it’s true that bees can see ‘colors’ we can’t. Many flowers have ultraviolet patterns on their petals, so bees can see these patterns. They use them as visual guides – like a map painted on the flower – directing them to the flower’s store of nectar. Some flowers that appear non-descript to us have strong ultraviolet patterns. Being a bee doesn’t necessarily mean you live in a more colorful world. Bees can’t see red – at the longer wavelength end of the spectrum – while humans can. To a bee, red looks black. Humans see light in wavelengths from approximately 390 to 750 nanometers (nm). These wavelengths represent the spectrum of colors we can see. Bees, see from approximately 300 to 650 nm. That means they can’t see the color red, but they can see in the ultraviolet spectrum (which humans cannot). Bees can also easily distinguish between dark and light – making them very good at seeing edges. This helps them identify different shapes, though they can have trouble distinguishing between similar shapes that have smooth lines – such as circles and ovals. Vision is important to bees, because they feed on nectar and pollen – and that means they have to find flowers. Bees can use odor cues to find a perfect flower, but that only works when they’re already pretty close. Vision is essential to help the bees find flowers at a distance. A bees Vision in responce to different colors: Red -> black Yellow -> yellow-green Orange -> yellow-green (darker) Green -> green Blue -> blue plus ultraviolet blue Violet -> blue plus ultra violet Purple -> blue White -> blue green Black -> black In conclusion, bees have a very unique color vision.
    2 points
  18. As advised by Mr. Fullerton, I did the Coat-hanger bubbles experiment to further understand flux! Pre-experiment preparation: First, in my closet I found a nice metal coat-hanger suitable for the trial. After attempting to reshape the coat-hanger, I learned that my hangers are very strong, or that I lack strength; so, I went to my brother's toolbox and grabbed pliers to help bend the wire into a slinky-like shape. My coil ended up having four turns. I then ventured into my kitchen to fill the sink with soapy water. With the bubbly solution complete, I was ready to start the experiment. The experiment: I dipped my wire coil into the water, and slowly pulled it out. I found that the bubbles didn't form well to the structure. So, I compressed the coil by pushing the turns closer together. When I tried again with the compressed coil, the bubbles formed nicely between each turn and along the outside of the coil. The formation of the bubbles between each turn demonstrated how the number of turns matter when calculating flux. Therefore, the more turns, the greater the flux. Hence, the equation for magnetic flux is: N=number of turns A=area within one loop B=magnetic field =angle between magnetic field and positive normal direction Everyone should try this experiment before the test on Wednesday!
    2 points
  19. 11/10 already and all i've read was the title.
    2 points
  20. While I was pouring ice cold lemonade for myself, I wondered-- "What would happen over time if I waited for a cup filled completely to the brim with ice to melt? Would the water spill over the cup as the ice melted? Or would the ice just melt leaving the cup still completely filled to the brim with no spills?" Huh. I had to test this out. I decided to use a cup filled with ice, and slowly poured water to the exact brim of the cup, and left a napkin under to see if the water would spill over after the ice melted. This was not enough for me. What if the cup were filled with ice and grape juice? Or ice cube grape juice filled with water? Or ginger ale? Or milk? I was curious. I tested these all out, only to find I was wrong in my original hypothesis. I was sure I'd come back to my kitchen a pooling mess of water, milk, grape juice, and ginger ale, but I was very wrong. I had three cups of perfectly filled glasses completely filled to the very very tippy top, like no other cup has even been. It was amazing. I realized something was up with water. These things called hydrogen bonds really mess with us chemist and physicists. Why? Because they can. In liquids, molecules slip, side, bond, break and reform. However when the water turns to ice, the molecules are rigidly bonded. This creates more empty space between the molecules when the hydrogen atoms bond together so rigidly and thus frozen water occupies more room. It is also less dense than liquid H2O because of this space. This is why ice floats in your Sodas. Or why in the winter-- better known as the constant weather in Rochester-- lakes and ponds freeze at the top and not on the bottom. Because ice is less dense due to H2O's molecular structure of Hydrogen bonding (positive to negative --oppositely charged ends of the water molecules-- creating space). Solid ice takes up more space than the liquid state of H2O. You would think that water would behave like every other substance from liquid to solid-- that the molecules would become denser and more compacted-- but no, it does the exact opposite. Because water is tricky, and that's why we drink it. You may be wondering why the milk and grape juice? Those are mostly water based as well, that is why. Due to the change in thermal energy, we all know that the water transferred energy from the high temperature (water) to the low temperature (ice). This is the second law of thermodynamics. It is also considered an energy heat flow. As we know, this happens so that this water glass can reach a happily balanced equilibrium. This is why ice melts. Even milk ice. The energy in the glass is never destroyed; the first law of thermodynamics tells us energy is conserved. Here are some cool links (pun intended) on ice and why it is less dense than its liquid state of H2O. (Also why it would not spill over a glass even when filled to the brim and left alone for an hour or so.) Not all science experiments have to be messy. http://www.word-detective.com/howcome/waterexpand.html
    2 points
  21. At the end of last quarter, I wrote a blog post about how I needed to change a few things because of the disaster that had come about in all my classes but especially physics. I feel that over the course of the past 10 weeks, I have changed the way that I learn and study. I find that I am more focused to get things done and understand them in a timely manner. I use all of the time given to me efficiently as well. Before this quarter, I found myself wasting class time and not doing the work that I needed to do in order to understand the content. Now that the learning is almost done for most classes and we move into the studying for exams during the last quarter, I need to remember the success that I have had during this quarter and continue it on. I know I can do it. We are now in the final stretch of high school and I am ready for it all. Until next time, RK
    1 point
  22. Close, but as the angle in radians approaches zero, cosine of the angle won't approach zero... it should approach 1.
    1 point
  23. Today was an unfortunate day in Physics class. After some bickering over some physics problem between my brother Jason and I, we decided that the only way to properly settle our dispute was to arm wrestle. Unfortunately, he beat me. Although I did not get the victory I deserved, I noticed that arm wrestling has quite a lot of physics to it. When arm wrestling, both people are trying to apply a greater torque than applied by the other person. Since torque equals the force applied times the distance from the point of rotation, the greater the arm length, the greater the applied torque. However, arm length plays a very small factor in terms of who has the advantage in an arm wrestle. According to Zidbits.com, "Stance, muscle density, stabilizer muscles, shoulder muscles, as well as where the specific tendons and muscle fibers attach to the bone are more important, and play a much larger role in arm wrestling. These same attributes are the reason why primates are generally much stronger than humans despite their smaller stature and size." In my opinion, Jason is not the true arm wrestling champion until he beats a primate. You've got a lot of work ahead of you @jcstack6
    1 point
  24. That's definitely a mistake you only make once. One burnt foot is enough.
    1 point
  25. Skydiving pretty interesting, but if my parachute didn't open, I would hope that I would have enough air resistance to slow me down enough to stay alive. I wonder how fast someone is actually falling before they pull the parachute.
    1 point
  26. I love the way you connected one of your favorite things to physics!
    1 point
  27. Good job Kyra! Maybe I'll see you in Disney.
    1 point
  28. Over Thanksgiving break, I had the absolute pleasure of getting the opportunity to meet Brother Guy Consolmagno of the Vatican. Brother Guy is the curator of the Vatican's Metorite Collection...or in simpler terms: the pope's astronomer. Sophie DiCarlo, of Irondequoit High School, God bless her soul, knows Brother Guy as her cousin; and knowing how interested I am in astronomy was able to set me up with the chance to meet and talk with him about his job as well as attend a lecture he gave to the parents of her younger brother's Boy Scout troop at the United Church of Christ this evening. Wow. That was a mouth full. While in the probable, four total hours I have ever spent in his presence, I learned innumerable random things about fzx and astronomy from Brother Guy that I simply haven't the time to go over in it's entirety in one blog, so I'm going to focus on the most amazing thing he physically set before us at his lecture earlier today. It was a rock. Well, there were multiple rocks. Some of them were LITERALLY 4.566 billion years old and let me say they looked real great for their age. There were these tiny little pebbly ones in a glass tube that has been parts of asteroids and another two that were pieces of metorites; however, ONE was super dark, compact and solid, while the OTHER was light gray, powdery and airy...if you can use the word airy to describe a rock. He called them 'rare.' I was so surprised...a RARE rock? Are you kidding. Rocks are not rare, welcome to Earth. BUT THEY WERE RARE ROCKS and I think that's absolutely astonishing. We weren't even allowed to touch any of these rocks because they we so rare. He said they had been on display. These were MUSEUM QUALITY rocks. I was just enthralled that there IS an existing rock that legitimate people would be actually mad if I threw it into a lake. Honestly, all this hype about rocks sounds pretty lame, but I am actually very excited about it...these little baby rocks are the T. J. Eckleburg glasses of the universe! I can't believe I was so close to them. Currently my cellphone is farther away from me than those rocks were not an hour ago. And 4.566 billion years ago those rocks were lost in space farther than I could ever imagine. Finally, he came upon a black rock. It looked like something a thug would kick around at a dump. It was awesome. He started discussing elements and what rocks are made of, typically silicon and iron, basic chemistry. And then explained that while there aren't a lot of air elements found in rocks, oxygen was in ALL of these rocks. But the 16-17-18 ratios were different because these rocks were formed in different parts of the UNIVERSE! The chemistry of these rocks was literally tampered with by the solar system...YES --> okay so important thing number 2: this black, dumpster rock he was talking about had CARBON in it...and everyone was like WHAT! And he was like yeah! Carbon? That's different than all the others! This one was also only 0.9 billion years old. Which, I mean, is a good life. But not nearly as long as the pebbles have lived. Point C => He then told us that in the largest sample of this rock, there was a stream of GLASS hardened down the middle. That means, that the surface of this planet must've carried LAVA. And in the glass strip, were BUBBLES which means there is proof of at one point: WATER. Also...it's rusted... Someone from the back of the room goes, "IT'S FROM MARS! Is it from Mars?" Brother Guy laughs and goes, "I'll tell you exactly why this sample cannot possibly be from Mars. You see...when we examine the size of the craters on the moon, we can evaluate how far they can launch debris. We can do that with Mars. And the craters on Mars are not NEARLY large enough to launch this chunk of rock to us." I was very impressed. I was convinced! Then Brother Guy goes, "Alas, from the data we have collected, the elements present and the comparisons we have made, this rock must be from a planet with the same exact, IDENTICAL, atmosphere as Mars." Someone else, "So it's from somewhere even farther away that we don't know about?" Brother Guy responded, "The thing is. How likely is it that there is another planet with the EXACT same atmosphere as Mars, that we do not know about, that is still close enough to have gotten remains onto Earth's surface? What are the odds? No chance. If there's one thing that I've learned about fzx, it's that if it happened, it's possible." If it happened, it's possible. I love that. I love that so much, I will never get over the fact that he said that. I think that's so clever. And true! He continued for just a second more: "So yes, this is indeed a sample from the planet Mars." And I was 11cm. away from it.
    1 point
  29. your dog should be a rapper.
    1 point
  30. And now we're starting to make electronics small enough that the wave nature of particles is coming into play. Quantum electronic devices are becoming reality, and gate thickness of transistors are becoming so thin that electrons tunneling through dielectrics becomes a problem (or a feature).
    1 point
  31. It is so cute that you were able make a bunny be a story and example to physics. What was your inspiration for writing on this topic?
    1 point
  32. I'm jealous. I remember when i had time to play some of these. Instead, last night's excitement include an episode of Sofia the First "The Emerald Key" -- some great dramatic tension at the end -- coupled with a trio of Elmo songs and reading two chapters of the third installment of the "Princess Tiara" book series.
    1 point
  33. Well let's be a follower and blurt out the same information as everyone else... Here we go. My names Corey, I play football and wrestle. I plan on joining the air force and becoming either a pilot or any other cool job I find out about. I am probably the only person taking this class that thoroughly enjoys science. I'm that person who sits at home and watches through the wormhole with Morgan freeman and thinks about the world and how we've come to understand it. I am also taking so bio (why? Because I can...) and I think Mr. Fullerton is super hilarious (true, but hoping he'll read this and I can grab some extra credit or something) and yeah that's a little bit about me. I am taking physics because well I'll say it once again I actually like science a lot. And also I just like knowing more stuff. Knowledge is power (yeah that's a Mr. Tytler quote) and I hope to be able to actually understand the mathematics behind some of the theories that I have heard about that fascinate and boggle my mind.
    1 point
  34. Good Evening Folks, I've received quite a few requests over the past couple months, and especially the past couple days, asking if I knew of an "outline version" of the AP Physics 1 learning objectives, essential knowledge, etc., organized by topic. I already had this created from working on the AP Physics 1 Essentials book as a chapter outline/roadmap correlated to the new AP 1 course, but had never bothered to put it in a user-friendly format to share. Well, until yesterday. Here it is: http://aplusphysics.com/educators/AP1Outline.html/ I understand this may not be the order in which you'd teach the topics, but for me at least, this organization is much easier to wade through and make sense of than the current AP Physics 1 and 2 Framework document (in which I get easily lost in the 200+ pages). Perhaps it will be of use to you as well. Please note that you can drill down by clicking on the triangles to the left of the topics, it's quite a big document if you expand it all out. I'm planning on doing this for AP-2 as well, though I probably won't have a chance to start on it until late July. Make it a great day! Dan Fullerton
    1 point
  35. I'm happy to see kphysics commented. looks like the end of course review will not be dreaded! jk
    1 point
  36. I see that you like to disc golf? that sounds very interesting to Shabba. Shabba would like to hear the physics behind, how you say, disc golf.
    1 point
  37. NO GO!!!!! Your fuel use is ridiculously high and inefficient. You will waste a ton of money on parts that will just crash back down on Kerbin because you don't have parachutes on them. And you will kill your Kerbal because there is no parachute on his cockpit. Rethink this one before launching.
    1 point
  38. How to calculate specific heat capacity of ice.specific latent heat of vapourisation of water,specific latent heat of fusion of ice, specific heat capacity of water? How will i know you have reply?
    1 point
  39. First try finding the charge in coulombs, then convert coulombs to electrons. This mini-tutorial may help: http://www.aplusphysics.com/courses/honors/circuits/current.html So, if you use q=It, solve for q in coulombs. Then, convert q (in coulombs) to elementary charges, or electrons, using 1 electron = 1.6*10^-19 C. Does that help?
    1 point
  40. http://www.youtube.com/watch?v=a19fhhJcs1E Although a bit lengthly the significance of this video takes a tour of the life and death of starts and what they have to offer in the universe. Also, some facts about stars include that it is large celestial body composed of gravitationally contained hot gases emitting electromagnetic radiation, especially light, as a result of nuclear reactions inside the star. Stars are wondrous things that we know little about because of our limitations in technology. However, we learn more and more each day. they come in a variety of colors and sizes. Blue stars are hotter then white stars, white stars are hotter then yellow stars. Red stars are the coolest Ive always wondered what would happen if the sun completely blew up while humans are still alive to witness it
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  41. after reading this, all I can say is BURR!
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  42. Very well done! Physics everywhere in volleyball. The video looks like a lot of fun -- we should make our own.
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  43. Great idea, and very well executed. Goes right along with what we're learning about the electromagnetic spectrum.
    1 point
  44. You're right, tons of physics in volleyball. As to the referee question, what happens when teams switch sides of the court?
    1 point
  45. Hi Everyone, As you may have noticed, progress on the AP-1 / AP-2 videos has stalled over the past few weeks… let’s just sum it up by saying that if it could have gone wrong, it did. First we had a database “miscue” with our previous web server host, in which we lost the better part of 9 months of posts from this blog. grrrrr. Then a stomach bug went through our house. And as I had all sorts of time to grumble over the increasingly poor response times of our site and the loss of the data (despite regular backups), I finally made the decision to switch hosts and get us our own virtual private server. What does all that mean, you may ask? First off, instead of sharing a bunch of computing resource power with hundreds of other websites, we’ve purchased a set amount of storage space, RAM, and CPU cores on a server that only services a couple web sites. Lots more resources devoted to our site means much more stable performance, and considerably improved loading speeds. It also adds a bit of complexity on my side, as well as a considerable increase in annual costs. I’m thinking about potential ways to offset that in the future, but in the meantime, I’m thrilled to have the site up and running the way it should be. Along with the server upgrade, we had quite a bit of “migrating” of programs, settings, and data to do. MOST of it went smoothly. One program, however, did NOT like the change at all, our Forums/Blogs software. I was already somewhat frustrated with the support and performance of our old system, so after a few days of beating my head against the wall (and getting mighty fired up at the technical support line), I bit the bullet and upgraded our system to the “Cadillac” of forum and blogging software. This, also, took a bit of time to setup, and because we’d already invested so much in all the student posts and work, I was able to hire an expert to assist in migrating all the data we could (what hadn’t been nutzed up by the previous software) into the new system. And he was gracious enough to give us a great price with amazing service due to the nature of our site (Thank you so much!!!). To help differentiate the old software from the new, and highlight some of the features of the new software, I’ve renamed the “Discussion” area on APlusPhysics “Community,” because really that’s what we’re trying to build. Not only do we now have forums (with some cool new features), and blogs (which even more cool new features), we also have a file repository where we can share electronic documents and programs with each other, we have an online chat system, we have tremendously improved calendars, the ability to better integrate “blocks” of content across the entire site, the ability to create custom pages (such as featured posts, highlighted material, etc. — I’ll turn this part on soon), the ability to incorporate e-books with direct downloads right from the site (instantaneous help!), even the ability to let members promote their good works to others across the entire site. Quite a few of these options I’ll be working on over the coming months, but as of today we have at least as much functionality as the old site, a much prettier graphic interface, and a fast, responsive, reliable site with a support team I have much more confidence in. So what’s next? Well, my first priority is finishing the “skin” of the system. It’s almost there. By the way, did you know you can adjust the color scheme of the site? See that little rainbow grid in the upper right of the community? Click on it and choose your color — whatever mood you’re in, the system can handle! Next, I have some behind-the-scenes work to do to tweak what shows up on the various pages… upcoming calendar events, latest files, users online, etc. They work currently, but I’d like to make their integration just a little more smooth. Nothing major, just have a bit of reading to do. Third, I’ve had quite a few requests to take my Powerpoint slides from the video series and make them available for teachers to use. This may be a bit more involved, as there are some licensing restrictions I’m working with the appropriate parties on, but I’m hopeful we can get something worked out in the not-too-distant future. Fourth, I’d like to get the featured content / topic pages built out. This will be an ongoing “as time allows” effort. This new system has tremendous potential to pull and organize information from a wide variety of sources, the question is “am I smart enough to make it work?” I’m hoping the answer is yes. Fifth, I’d really like to work to promote the downloads section as an area where we as physics instructors can share the best of what we put together for our students. There are both public and educator-only folders, and I think this has tremendous potential to be a great resource for us all, but I’m betting there will be quite a bit of legwork to “sell” this concept to other physics teachers across the world, so that it becomes not just a place for folks to download my work, but a place where we can all collaborate and share with each other. In this, I definitely need your help. If you would, take a minute or two and find one original lesson, worksheet, lab, hands-on activity, whatever… upload it to the “Downloads” section and share it with the rest of us. Can you imagine what a wonderful resource we’d have if each physics teacher shared just one or two amazing activities? Imagine if we then started building off of those… then again and again… we’d have the greatest teaching resource of any discipline (and we’re already well on our way!) Sixth, work hasn’t stopped on the physics videos. I have to admit I’m a touch burnt out after finish the AP Physics C series this year (both Mechanics and E&M), and completing an entire AP-1 / AP-2 sequence for Educator.com (which is currently branded as AP-B but was set up with the new courses in mind). I’m continuing to plug away on the optics section of AP-B, and have a few more pieces to fill in. Once I get through this week my hope is to complete at least one more video per week for the foreseeable future. Last, but not least — I’ve spent the past year doing pre-work for an AP-1 / AP-2 guide book for students (in the vein of Honors Physics Essentials, but specifically directed toward AP-1 / AP-2). As we get to the end of the school year, I want to focus on the BIC (butt in chair) strategy to get a first draft underway. I have tons of notes, outlines, and materials, and from past experience once you get rolling it’s not so bad, but I need to take those first few steps. I just want to make sure I have all my other “gotta get done’s” out of the way before I dive headfirst into this one for the summer. Thanks for all your support, and I look forward to seeing you on the new APlusPhysics Community (by the way, if you haven’t tried it out yet, we’d love to see you! Shoot me an e-mail if you’re a professional physics instructor and I’ll get your access upgraded so you can see into the “teacher-only” parts of the site as well)! Source
    1 point
  46. 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 room because the door acted like a plunger, increasing the volume of my room faster than air could enter and decreasing the pressure inside. with my window open, gas can come in both through the window and through the crack under the door, increasing the speed at which air could enter, therefore decreasing the difference between the rate of incoming air and the rate of increasing volume. with this difference smaller, the door does less work on the air inside because it doesnt need to decrease the pressure to close. with the window closed, i was used to giving more speed to the door to close it, but now that the window is open and less of the energy i give the door is used to change pressure, the speed i usually use is too much, and the door slams.
    1 point
  47. And sorry to keep adding to this... but upon further investigation - you might want to be in Pascals (does that sound farmilar lol?). That is in N/m^2 so you will need to figure out how many m^2 you have from cm^2. There are 100 cm in a m, so 10,000 cm^2 in a m^2 (100x100=10000). Divide your area given by 10,000 to find how many m^2 you have instead and then plug that number into P=F/A as the A instead of in cm^2 and you will have your answer in pascals.
    1 point
  48. well you know 3 could because if you put 3N and 4N at 90 degrees there resultant would be 5N, so if you put the 5N in the opposite direction of the resultant the object would not move. 2 could work too, because if you set it up so that the 3 2N forces were 120 degrees apart, a peice, you would be able to achieve an equilibrium (draw it!) Now that i think about it, the answer is 1. 1 could not have an obtainable equilibrium. When you put the other ones at funky angles you can always achieve an equilibrium. BUT, for number 1, even if you had the 5N force going one way, and the 1N and 3N force ON TOP of eachother heading in the exact opposite direction, you could not add up to the 5N needed to attain an equilibrium. Adding an angle between the forces only reduces the resultant (there is no sinx or cosx value bigger then 1). So to do this problem, the first step would be to see if 2 of the resultants can add up to be greater then or equal to the other resultant in all cases. For number 1, 1N + 3N < 5N, so it would be impossible to have an equilibrium
    1 point
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