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  1. 3 points
    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!
  2. 3 points
    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!
  3. 2 points
    ...(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.
  4. 2 points
    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..
  5. 2 points
    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.
  6. 2 points
    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?
  7. 2 points
    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.
  8. 2 points
    Maybe I'll write a post just about cows...*suspense*
  9. 2 points
    Sweet blog post. If you wouldn't mind spreading the love and also buying your two student teachers silver Porsches, we wouldn't complain
  10. 2 points
    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
  11. 2 points
    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!
  12. 2 points
    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).
  13. 2 points
    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.
  14. 2 points
    Yay coat hanger! I hope you don't mind, I posted on this topic too but cited your blogpost in it. Nice work here
  15. 2 points
    11/10 already and all i've read was the title.
  16. 2 points
    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
  17. 2 points
    Glad to hear you were able to get that coathanger bent and see the continuous shape that the solenoid makes with the soap bubbles!
  18. 1 point
    This year, I really pushed myself with new challenges that were difficult, but also very rewarding. I took on the challenge of a flipped classroom and learned a new way to be a student that will help prepare me for college. While at times it was a struggle to keep up, this course kept helped me prepare for college by forcing me to work on my time management skills. I think that I have a lot more of improvement to do on this, but I have come a long way from the beginning of the year. I think before I go to college, it might be a good idea to review Dr. Chew's videos and brush up on some of the proper learning techniques that he taught. Another new thing that I took on this year was completing blog posts for this class. This activity taught me a lot of new things about how what we are learning in physics applies to the real world and I really appreciate all that I have learned. Going forward, I will have to apply the math and physics of the classroom to the real world, and doing the blog posts gave me a little bit of insight into the connections between the two. Although it may have been a challenge at times to complete the necessary blog post on time, I enjoyed learning new things about the world around me.
  19. 1 point
    The clean and jerk is an Olympic weight lifting movement where the lifter pulls the the bar from the ground, catches it in a squat, stands up from the squat and thrusts the bar over their head. The clean is performed by pulling on the bar off the ground with a high velocity, once the bar reaches about chest height, the lifter drops under neath the bar and catches it on his shoulder, and sits in a low squat position. The lifter then pushes up with a high velocity to stand back up, this is the clean. The jerk part of the movement is fairly simple. The lifter dips their hips down how ever far they desire, then they thrust the bar up with a high velocity, kick their legs out in a lunge position, catch and hold the bar at rest above their head.
  20. 1 point
    Thinking about what we have been learning in physics, on the topic of energy, it makes it more clear to see some of the physics that goes into taking a shot in hockey. I mean they go so fast but getting there was a little hard for me until this unite that we are in now. Looking at elastic potential energy you can clearly see that in the picture below. It's crazy to see how that potential energy is turned into kinetic energy in fractions of a second and the puck is sent flying at ridiculous speeds.
  21. 1 point
    Prior to the beginning of overtime in last weekend's Packers v. Cardinals game, referee Clete Blakeman (definitely sounds like a fake name) attempted to flip the coin. Except he didn't. The coin did not flip at all. This prompted an outburst from Packers quarterback and insurance salesman Aaron Rodgers, who demanded a reflip. Blakeman obliged and the Packers subsequently lost. But how does a professional who has likely flipped hundreds of coins in his lifetime manage to screw up like this? Excluding potential sabotage, the only explanation for the lack of a flip is physics. A coin is flipped by exerting torque on one side of the coin and creating rotational acceleration. This allows the coin to spin through the air like some sort of spinning thing going through some other kind of thing. However, if the force is applied directly at the center of the coin, there will be no torque as the distance from the axis of rotation is zero. Therefore, the coin will not flip and everyone will be upset. But there is another factor as well. The coin used was comically over-sized and, based on the NFL's wealth, made of Lil' Wayne's melted-down teeth. This gave the coin a much higher mass and radius and therefore moment of inertia. An object with a high moment of inertia is more difficult to accelerate. This allowed Blakeman to be just a little off from the center of the coin and still have the torque be negligible. Clearly, Blakeman is both a physicist and a Cardinals fan.
  22. 1 point
    Now that I've reached the last blog for this quarter, I thought I'd take it full circle back to music. Specifically the drum set. Drums are known for being loud and helping other members in a band keep the beat of a song. This is due to how they are built. Let's talk specifically about the bass drum. This is the largest drum, seen on the bottom of the drum kit and normally played with a foot pedal. The reason that it's the biggest drum is so that it can make those loud, deep sounds. The foot pedal strikes the skin of the drum, causing it to vibrate. This vibration sends the sound waves out through the drum, where they bounce around the inside of the drum. Having such a wide radius and depth, the drum allows the sound to reverberate within the drum before heading out to greet the audience's ears. This keeps it at a low frequency and allows the sound to build up and strengthen, becoming louder and reaching farther before dissipating.
  23. 1 point
    New Aluminum Battery Could Recharge Your Phone in Just One Minute The next generation of batteries is here! An ultrafast rechargeable battery that’s also cheap and long-lasting. And since the new material it is made of is aluminum, the new battery is a safer alternative to conventional lithium-ion and alkaline batteries we are using all around the world today. For decades, Scientists have tried to use aluminum as material for batteries. The great benefits of aluminum over conventional lithium-ion and alkaline batteries that we are using today are that aluminum is cheap, bendy, and has low flammability and high-charge storage capacity. So far all attempts to develop a commercially viable aluminum-ion battery have been unsuccessful. But now for the first time in history, an international team led by Stanford’s Hongjie Dai have accidentally discovered a simple solution. I’m not a Scientist, but if you are really interested in the procedure, I would highly recommend you to check out this article (http://www.nature.com/nature/journal/vaop/ncurrent/full/nature14340.html#figures). The battery is also ultra-fast charging and crazy durable. Unlike the hours some of us might spend charging our phones every night, the prototype of the aluminum battery has a charge time of one minute! And not just that but what most of us don’t know is that the batteries for example in an iphone 6 are made to last for about 500 to 700 cycles, were the international team of scientists says that their new battery is able to do more than 7,500 charge-discharge cycles without losing its capacity. Unfortunately, the technology is still not completely developed and won’t be on the marked any time soon. One battery generates about two volts of electricity. While that’s more than any other aluminum prototype thus far, that’s only about half the voltage of a typical lithium battery. That doesn’t mean that it won’t come at some point though but it will take a little more research over the next years and then there should be nothing to stop the new era of batteries that are not just faster but also better for our environment. Also the scientists are confident in their next steps “Improving the cathode material could eventually increase the voltage and energy density,†Dai explains. “Otherwise, our battery has everything else you'd dream that a battery should have: inexpensive electrodes, good safety, high-speed charging, flexibility, and long cycle life. I see this as a new battery in its early days.†If you want to know more check out this video:
  24. 1 point
    Great post! And to add some trivia, Zooey Deschanel also sings two songs, including the title track, in the recently released Winnie The Pooh movie!
  25. 1 point
    Physics is simple once you get the hang of it! At first the concepts are confusing, but practice makes perfect and it becomes much easier. By the time the test rolls around it's much easier. When I look back on my tests I wonder why I ever had trouble with the chapters. I am so glad I can say this now!


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