Jump to content

Leaderboard


Popular Content

Showing content with the highest reputation since 11/14/2010 in Blog Entries

  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. 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.
  3. 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..
  4. 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.
  5. 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
  6. 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!
  7. 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).
  8. 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.
  9. 2 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!
  10. 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
  11. 1 point
    A common underestimation of our forebears in their histories and scientific achievements is that it was common in many archaic cosmological models that the Earth was a flat, disc-like plane. Without a doubt, there are people that persist to this very space-age day that trust in a flat Earth but it was in no way exclusively an ancient phenomenon or a common one. Even with few scientific instruments, the elder humans, unequipped with the internet and latest edition of The AP Physics C Companion: Mechanics (full color edition) by Dan Fullerton for only $19.99 on Amazon and free shipping with Amazon Prime, saw how boats would disappear over the horizon and observed that the stars would seem to swirl about an axis which also was an idea supported by the Christian church. The idea that people did not know the Earth was round stems from several fabrications made to support a popular thesis at one point that religion and science could not co-exist. Which brings me to this point: the resurgence of the Flat Earth Society. It is caused solely by social media's way of spreading disinformation and allowing people to assemble into a Facebook group of over thirty thousand apparently sincere believers of a flat Earth model. So I leave off with question: should you even believe in this post because it is social media?
  12. 1 point
    In the spirit of Halloween, I created a spooky story that links together a couple of multiple choice problems from the Work, Energy, and Power exam that we took on Wednesday 10/25 last week. I hope you enjoy and Happy Halloween! A person pushes a box across a horizontal surface, but there is so much more to the story. The boy pushing the box across the creaking floorboards of a desolate hallway looks over his shoulder, fearing for his life. Someone had blackmailed him into bringing the 40 kilogram package to room number 207 in the haunted hotel on Mansfield Street, so he put all 20 bottles into a box and went to the hotel precisely at 10 o’clock. Despite the fact that his bones were shaking, he continued to push the box at a constant speed of 0.5 meters per second. The box slides along the dusty floor with a coefficient of friction of 0.25 and creaks with every step he takes closer towards room 207. He reaches the door and slowly enters. The first thing he notices is a massive grandfather clock covered in cob webs that stands directly in the center of the room. Its frictionless pendulum has a length of 3m long and swings with an amplitude of 10°. He stares long and hard at the clock as its pendulum swings from its maximum displacement where it has a potential energy of 10J, to its lowest point at vertical position where it has 10 J of kinetic energy. But he knows that somewhere along its path it has an even amount of both kinetic and potential energy of 5 J. He is so mesmerized by the massive clock that he doesn't hear a 2000 kg car accelerating from rest at 3 m/s^2 down the street. Lucky for the boy, the car goes by the hotel at a speed of 20 m/s. With his eyes still transfixed on the clock, moving in sync with the clocks pendulum, he begins to feel like he is floating in a void of black space. The clock is the only thing in sight besides darkness. Suddenly he is blinded by a flash of bright lights and the sound of loud screaming fills his ears. As he snaps back to reality and his eyes begin to adjust to the light, he realizes that he is surrounded by a large group of grotesque zombies that are slowly closing in on him. He grabs on tightly to the massive grandfather clock and squeezes his eyes shut. A cold hand touches his shoulder and he lets out an ear piercing scream. Just when he thinks he has reached the end, he hears laughter. Upon opening his eyes, he recognizes the faces of the zombies. They are his friends! And they have thrown him a surprise birthday party inspired by his favorite TV show, The Walking Dead! Good thing that he brought the soda! Happy Halloween y'all!
  13. 1 point
    This week on Wednesday, I had to get an MRI for my knee to make sure everything was ok after I injured myself playing soccer a couple weeks earlier. While I was there, I was very curious about how the whole process worked and how it relates to physics so I did some research and here is what I found. In an article from medicalnewstoday.com titled MRI Scans: All You Need To Know by Peter Lam, I learned that "an MRI scanner contains two powerful magnets" and "upon entering an MRI scanner, the first magnet causes the body's water molecules to align in one direction, either north or south." So this is why I had to take off my earrings before going into the scanner because otherwise it would've been attracted to the magnet and cause problems. I then learned that "the second magnetic field is then turned on and off in a series of quick pulses, causing each hydrogen atom to alter its alignment and then quickly switch back to its original relaxed state when switched off. The magnetic field is created by passing electricity through gradient coils, which also cause the coils to vibrate, resulting in a knocking sound inside the scanner." This would explain why the machine was so loud and I had to wear headphones to block out the noise. But luckily, I got to listen to some country music to block out the sound of the banging. The scanner then detects these changes "and, in conjunction with a computer, cman create a detailed cross-sectional image for the radiologist to interpret." Lucky for me, my MRI showed that my knee looked very good and my injury was most likely a bone bruise. MRI's are very helpful tools for diagnosing patients and getting a better look inside the human body and I can appreciate knowing a little bit more about how they work! Visit: https://www.medicalnewstoday.com/articles/146309.php to read the full article.
  14. 1 point
    Everyone seems to skip leg day, not me!!! Leg day is by far my favorite, especially back squats (I can back squat 365lbs ladies ). While the back squat is a simple movement, it requires tremendous power in your legs. To perform a back squat you must place the bar on the back of your shoulders, lower your hips down bellow parallel and bounce out of the bottom of the squat . Once you bounce you will reach a spot in the lift where you will have to push down on the ground in order to push yourself and the bar up. The back squat involves a lot of momentum and a very big impulse. The impulse occurs during the bounce at the bottom and without a large enough impulse you will fail the lift. Don't skip leg homies, leg day is the best day.
  15. 1 point
    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
  16. 1 point
    I watched a cool lab video on a professor giving a visual representation of gravity. The idea of gravity has always been pretty easy for me to understand and easy to use in equations but where I begin to lose that understanding is when we leave earth and look at how it holds everything together. How space is constantly expanding but these planets, moons and stars are constantly effecting each other. In this video you get to see how gravity really makes these things work together to make space what it is. The part I found coolest was when he explained and showed why all the planets are going around the sun the same way. In this case it is clockwise and anything going the opposite way around the sun was or would be eliminated. This was due to collisions and as he says, those going counter clock wise were not heading in the 'preferable direction'.
  17. 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.
  18. 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.
  19. 1 point
    The European Organization for Nuclear Research known as CERN was founded in 1952. Since then more than 80 countries have been contributing to the research done in the particle accelerator and trillions of dollars have been invested. Many argue that the money spent could have been invested in humane projects rather than spending it on research of tiny particles in huge machines under the ground that go through multiple countries. But most of us don’t know the great benefits the research provided us in the past years which greatly justifies this investment. The research provided the discovery of cancer therapies, monitoring nuclear waste, helps to save tons of electricity in power transmission, the discovery of the MRI, and the greatest of all a better understanding how our Universe works.
  20. 1 point
    Hey guys! Over spring break we drove to Disneyworld in Florida. The car ride was unbelievable long so we decided to stop at a few places. One of the stops was the Kennedy Space Center in Cape Canaveral. For the first time in my life I saw a real rocket last week, which has been a dream of mine since I was little. One of the things I always wondered was how rocket engines work and what makes them so unbelievable strong..? Like most engines, rockets burn fuel. Most rocket engines turn the fuel into hot gas. The engine pushes the gas out its back. The gas makes the rocket move forward. Rockets work by a law that we have all learned a couple months ago; Newton's third law of. If you remember it, it says if Object 1 exerts a force on Object 2, then Object 2 must exert a force back on Object 1. Moreover, the force of Object 1 on Object 2 is equal in magnitude, or size, but opposite in direction to the force of Object 2 on Object 1. In other words, for every action, there is an equal and opposite reaction. The rocket pushes on its exhaust. The exhaust pushes the rocket, too. The rocket pushes the exhaust backward. The exhaust makes the rocket move forward. Actually quite a simple concept.
  21. 1 point
    Since 3 years I’m playing rugby for the RC Danube Junior Pirates in an international league. This following summer we’ll play against a team from South Africa and France and I’m already really excited! I am currently playing 1st row tight head prop which would be a forward in soccer. Every time somebody makes a mistake or brakes the rules a scrum is utilized. In the position I’m playing I am in the first row for the scrum which happens pretty often. For most of you who have never heard about a scrum (short for scrummage); it is a method of restarting play in rugby that involves players packing closely together with their heads down and attempting to gain possession of the ball. With all that said there is a ton of physics involved! The shoes that are rubbed into the grass are giving me a good grip because of the resistance the dirt is providing. Every player gets pulled down by gravity and is only able to maintain in this position because they lean against the opposite team. Which team then has the grater inertia and stronger players will push the other team away and gains possession of the ball. A year ago I would have never thought that there is so much physics even in a rugby game
  22. 1 point
    Before I finish off my Shrek series I had a few more thoughts on adhesives. One being, the fzx behind Post-it® notes. I recreationally collect sassy Post-it® notes. You'd be surprised...but they are always applicable. Imagine having the printed phrase, "If ignorance is bliss, why aren't more people happy?" on hand every second of the day. It's exhilarating. Or something like, "Why yes, I am overqualified." And maybe, "I think you heard me the first time." They're so so so useful, and I highly suggest investing. Anyways, I've only had a mere use, not quite a reason. WHY do post-it notes work? I did some research from a website that described life on Earth as, and I quote, "[A] bit like being a giant living Post-it® note—only with legs!" so I think my information is fairly reliable. With my collected data, I learned that: A.) The back of a sticky note contains a continuous film of adhesive as well as microscopic glue bubbles. [These can only be seen with an electron microscope]. B.) These glue bubbles are called microcapsules and they are about ten to one hundred times bigger, but much weaker, than the glue particles on the average and conventional Scotch Tape®. C.) When pushing a sticky note into place, som of the larger microcapsules cling; just enough to support the weight of the tiny slice of cute yellow paper...hopefully decorated with a sassy phrase. Well. There you have it folks. Just a quick and simple lesson on one of my quirks as well as as the fzx behind it. One piece of advice I'd like you to take home with you tonight: Just remember, that every time you attach and peel off a Post-it® note, dust and dirt attach to the adhesive capsules. Therefore, the notes prgressively and gradually lose their stickiness. Sure, it WILL go on sticking for awhile. Alas, Post-it® notes are a thing to be valued. So don't waste their magic. I mean fzx.
  23. 1 point
    The Bug-A-Salt sure looks like a great invention utilizing tons of physics -- notice the free body diagram at the beginning of the video!
  24. 1 point
    In Football Newton's 3rd law of motion is in action. When a running back is running head on against a tackler who is running just as hard and fast the outcome may vary. In games there are times where the running back gets hit so hard that he fumbles and other times the running back pancakes the tackler. One of the biggest factors is the mass because the forces are creating equal and opposite reaction. Force is applied and transmitted back. The player with more mass will generally hit harder.
  25. 1 point
    This is mine and Michalla's catapult. We are excited to launch tomorrow although it does not throw a very far distance. Prior to building it, we did not do any calculations. We built it by eye and what we thought would launch the best. Even though it is not amazing, we are proud of how it came out because at first we never thought us two could build one. If we were to do the project again, we would keep in mine that if it was angled at 45 degrees, it would travel the farthest. Also, if we used some sort of springs we think that the velocity right after the softball leaves the lacrosse stick would be higher. Lastly, from watching lacrosse games I know that lacrosse sticks are often broken. From being in physics class, I now know that all forces come in pairs (Newtons 3rd Law). This has been starting to make me nervous because as the catapult is exerting a force on the softball, the softball is exerting the same force back onto the catapult. If the project wasn't tomorrow I would think about changing what I used to build it for this reason. It should be fun to see what happens tomorrow.
  26. 1 point
  27. 1 point
  28. 1 point
    I happen to both be a Boy Scout as well as a physics student which I believe to be probably the coolest combination ever. Sooooooo, I decided to apply my physics knowledge to my Boy Scout skillz! On a recent campout to the Pennsylvania Grand Canyon I decided to bring a hammock as a lighter alternate to a tent since I would be hiking around 10 miles. When I packed my things I decided to just grab some random rope from my garage for my hammock... which could have been a bad idea! Luckily the rope held up but I decided to find just how strong the rope had to be! Now the hammock was strung up between 2 trees with knots on each side and me in the middle. I weigh about 170 pounds or 77.1 kg which will be very important in finding tension or "T". Since the hammock is in equilibrium we can use Newton's 2nd Law to find T. The net force in the x direction on the right is equal to the net force on the left. Since both ropes were at about a 30 degree angle we can then say the Tensions are equal so -Tsin30 + Tsin30 = 0. Then since ups must equal downs we can say 2Tsin30 = mg or rewritten T = (mg)/(2sin30) which gives us T! Now lets plug in numbers T = (9.8x77.1)/(2sin30) or T = 755.8 Newton's. That was the tension in the rope of my super comfortable hammock. Maybe in a future blog post I will determine just how strong that rope was... or maybe not that could be quite challenging... The average strength of say paracord is about 250 pounds or 1107.4 Newton's and what I was using was certainly not as strong as paracord! So I guess this times I can count my lucky stars I wasn't sleeping on the ground, and maybe next time I should BE PREPARED with some stronger rope!
  29. 1 point
    I'am sitting in the Basement of our house right now, thinking about what I could write as a blog post and next to me Quinn works out. It is amazing what a difference it makes for her if she uses the 25lb or the 50lb weight. I'm sure she could do 15 repetitions with the 25lb on her exercise she does right now, but if it was 50lb even 5 reps would be very hard.... So why does it make such a big difference which weight she uses? --> It is Physics! The gravity on earth pulls down her weights and as bigger the mass of the weight is as grater the force which pulls it down. Unbelievable that Physic is in every little thing we do!
  30. 1 point
    To start, I apologize for a fourth consecutive video game physics blog. But I somewhat recently splurged on a new game that I think demonstrates a point I touched on earlier - video game physics are becoming more and more visually impressive. Destiny is developed by Bungie, a well-loved company that brought the masterful Halo franchise into the gaming world. It's a quite repetitive adventure, and flawed in several ways - but gameplay aside, both fans and detractors agree that the game looks incredible, depicting the solar system (well, parts of it) beautifully. (The game's dancing physics were actually perfected by Paula Abdul herself. Not really though) Destiny uses a physics system developed by the company Havok, who are well-renowned in the world of gaming physics. It relies heavily on physical simulations and collision physics, both of which are prevalent here. Things like a character's hair or cape will actually show realistic signs of movement while running, etc. By blending vibrant artistry with actual soft body simulations, they believe they have the cutting edge technology to bring to life the exciting world of computer-generated foliage. In all seriousness though, these superficial little details truly show how much gamers care about graphics, and how fluently the game moves. And, I'll be the first to admit, these details do significantly increase the immersion factor while playing. It's one of those games where you just have to stop every once in a while and look around. My favorite use of this physics system though is without a doubt the Sparrow mechanics - a Sparrow being, of course, an all-terrain space hover bike. It's unrealistic...for now. For an added bonus, we note how the thrust of the engine in the back of the bike propels the bike forward, due to Newton's 3rd Law, which not-so-surprisingly, holds up pretty well in space. But also note how the bike seems to instantly lock on to the gradient slope of the terrain it hovers over, a pretty interesting physical phenomenon that permeates the whole game. All of these crazy, futuristic weapons and gadgets seem far off, but we never know if something like this could end up coming into fruition. Check out, for instance, a "fusion rifle". Could we ever harness the energy to create something like this? I mean, if its name is accurate, I assume it generates energy through the process of fusion - yes, not fission, FUSION - going on INSIDE some kind of fusion chamber in the rifle. In like a split second. (And we don't even know how to do fusion yet, so we better get on it if we want to stand any chance against the aliens.) To conclude, though, I'll quote the ever-popular video game aphorism: "Graphics aren't everything." And that's certainly accurate. You can create a beautiful game with inspiring physics engines that still manage to disappoint thousands and thousands of gamers - that's what happened here. This game is now the most popular new game franchise of all time, and its budget was a whopping half billion dollars. Yeah, with a 'b'. However, it gives us gamers a friendly reminder that if the game doesn't play well, all of this money is for naught. Destiny's story doesn't hold up at all, especially looking at Bungie's Halo series, which had beautifully done storylines. This isn't to say Destiny's bad, I personally enjoy this game - but it certainly won't satisfy anyone looking for a storyline that's followable - or even coherent. So here ends my rambling Destiny physics-discussion-review-hybrid blog post. Hopefully it helped anyone on the fence make a decision to purchase it or not - and if not, tune in for my next post. Which is hopefully about something other than video games.
  31. 1 point
    What's this? New AP-C students? Welp a new dawn has... dawned and I have made the short stroll of 18 miles to RIT. So what has changed? Not much. Right now you AP-C'ers are taking, I assume, mostly college level courses and believe it or not they are actual college level classes, like no joke. With Calculus, Physics and other classes I was (and you are) taking the equivalent of a Freshman year in college. If it sounds intimidating its because it is, taking that big of a step a year early is very tough and will, at points, seem like the worst decision of your life. Don't get me wrong senior year is lots of fun, but remember, if a class like Calc or Physics is getting you down, hold on. At some point or another you will have to realize that not all knowledge is easy to learn and high school is the best place for that. Mr. Fullerton is amazing and he, unlike a college professor, will help you through every step if he needs to. Enjoy yourself and make it a great year! Oh yeah, READ THE TEXTBOOK (I have to pay for mine, use it while it's free) Have fun and stay classy, Shwiby
  32. 1 point
    Physics is.. so gosh darn great I feel like it and I... are fate. With a Newton here, or a Pascal there, These SI units we love and share. Whenst look for a potential mate, All emotions to physics, they equate. If the air in the room feels perhaps electric, Just know that physics isn't eclectic. A standard mix of fun and function, Studying physics fills one with compunction. Alas, alack, it is time to go, I'll need to do work, that's fo' sho'. As Bernoulli said, just go with the flow. So shine like a lumen and simply glow.
  33. 1 point
    First of all I have to say that I'm surprised that nobody here has blogged about this yet. But in case you haven't heard yet, March 17th was a big day for science, and physics in particular. Researchers from Harvard University and the Smithsonian released evidence of distortion in the cosmic background radiation (shown to the right) caused by gravitational waves from when the universe went through inflation after the big bang. The idea is that in the 1x10-35th of a second after the big bang the universe expanded very rapidly at a speed much larger than the speed of light (and yes, that is possible since its the universe itself was moving). So what exactly does this mean? First of all, it is direct evidence that the big bang happened. There still may be a little uncertainty but the team that found this distortion has been looking at it for three years ruling out every other possibility so chances are it's exactly what they say it is. It also may have profound effects on our understanding of physics. Gravity waves were the last untested part of Einstein's theory of general relativity and with this evidence its now a complete theory. There is also a chance that it may lead to a unified theory of modern physics. As of now general relativity (the physics of very large things) and quantum mechanics (physics of very small things) don't work together but this discovery could help bridge the gap between the two. Also, most of the current theories of inflation include the existence of multiple universes and this evidence narrows down the theories a lot to the ones that include a multi-verse. The possibilities with this are endless because there is a chance that other universes will have laws of physics different than our own, which would be crazy but awesome to study. Scientific breakthroughs of this magnitude don't happen often but when they do they usually lead to a vastly improved understanding of the mechanisms of the universe.
  34. 1 point
    Physics class is becoming very interesting, especially through this circuits chapter. I am learning about series and parallel, and the different formulas that are applied for each. I have also learned about Ohm's Law (V=IR). At first it was difficult to remember the different formulas for both series and parallel circuits, but after doing many VIR Charts, the work has become a bit simpler. I have learned a few things for both series and parallel circuits Series: Electric Current (I) is equal all the way through = I1=I2=I3 Parallel: R = (R1-1 + R2-1 + R3-1)-1 Also, this Kahn Academy video has explained a little more for me! www.youtube.com/watch?v=3o8_EARoMtg
  35. 1 point
    What is Pavel time? Pavel time is the time right before a deadline when actual work gets done. How does this relate to physics? It relates specifically to Albert Einstein's theory of relativity. Part of the theory of relativity states that measurements of various quantities are relative to the velocities of observers. In particular, space and time can dilate. So, in real life, as an object approaches the speed of light, it gets squished and time slows down for the object. How does this relate to Pavel time? In my theory of relativity, as more work gets done more quickly, time slows down and allows me to finish whatever assignment I have before the deadline.
  36. 1 point
    So It gets dark before 5 O'Clock nowadays. I state this not becuase I think you, the reader, are incable of interpreting a clock ( I assume you are because you are literate enogh to read ) but because this fact has some bearing on the phyisics of running. When I foolishly decided put off starting my training run untill four fifteen, I found myself in the middle of the woods forty minuites later with the sun sinking below the horizon and three miles of trails left to navigate. Phyisicly speaking, A couple things happened to me at that point. First, the subconience fear kicks in, the effect of too many horror movies, that I will be eaten by cyotes or kiddnaped or murdered by some deranged phycopath. This produces the aldrenaline rush, which sends me flying throgh the woods at an abnormal speed. Because every shadow is a potential lurking threat to my scared brain, I fail to look at the ground, and I forget newton's third law. Applied here, that means that when sneaker toe applies force to an unseen root, this root will push back and cause a runner to accelrate downward in a parabolic arc toward the ground, because his momentum will be stopped suddenly and unexpectedly. Thankfully, I cauhgt myself and managed to keep my fear under controll for the rest of the trip back. But a runner will stay in motion at a constant speed unless acted upon by the completion of his goal, and I ran, abiet carefully, all the way home. Moral of the story: always bring a flashlight. P.S. don't judge me on the spelling my laptop does not have a right click and I have no way to spell check that I know of. You know you all rely on it as much as I do:)
  37. 1 point
    Here's something I just stumbled upon a few minutes ago. Its Olympus Mons, Mars' largest mountain. Olympus Mons is also the largest volcano in the solar system and the 2nd tallest mountain in the solar system (behind the Rheasilvia peak on the asteroid 4 Vesta). Olympus Mons is a shield volcano and was formed the same way that the Hawaiian islands were, by lava flows hardening and building up over hundreds of millions of years. The difference is that while the Hawaiian chain was formed by Earths crust moving over a hot spot in the mantle, Mars does not have mobile tectonic plates so the hotspot that releases lava is always in the center of the mountain. Olympus Mons is located near the martian equator and is 370 miles wide and 13 miles tall, with cliffs up to 5 miles tall. The base covers an area roughly the size of the state of Arizona and is 2.5 times taller than mount Everest. The atmospheric pressure at the highest point is estimated to be 0.03kPa, which is 12% of the average martian atmospheric pressure of .6kPa. What's interesting about this is that the air pressure at the summit of Olympus Mons is a much higher percentage of the surface pressure than it would be on Earth. The atmospheric pressure on Earth at an altitude of 13 miles is approximately 4.5kPa, just 4.43% of the average sea level pressure of 101.33kPa. This happens because the acceleration due to gravity on mars in 3.7m/s2, less than half of that on Earth, which increases the scale height of Mars' atmosphere, so there is relatively higher atmospheric pressure at higher altitudes. It's amazing to think that there are mountains out there on other planets that dwarf anything we have on Earth. I've always been interested in space but my interest just peaked (pun intended) as I look out at the night sky and wonder what else is out there.
  38. 1 point
    Yesterday I climbed Giant Mountain, one of the 46 Adirondack High Peaks. With a summit elevation of 4,627 feet (1,410 m) Giant is the 12th tallest of the high peaks and with an elevation change of 3000 ft in 3 miles it's also on of the steepest. The journey began at the car near the trail head where I was deciding on footwear. The 2 options were hiking boots (0.92 kg a pair) of Nike frees (.42 kg a pair). The boots would be heavier and require more work to ascend the mountain, but would provide better traction and keep my feet dry. The frees would require less energy but likely slip on everything, provide less support and get my feet drenched within minutes. I chose the boots, so how much more work did I do climbing the mountain? The ideal approach to figuring this out would be to multiply the number of steps that I took while ascending and descending the mountain by the average distance that I lifted my feet with each step; and then multiply that by the force I exerted against the weight of my boots/shoes (work=force*displacement). However I didn't count my steps because counting for 5 hours would have driven me insane and the vertical distance that I lifted my feet varried widely on the diffenrt sorts of terain I encountered. So I'll just use the vertical displacement up the mountain as my displacement. The difference im energy expendature can be found by multiplying the difference in weight of the shoes by the displacement up the mountain. Difference in weight=(.92kg-.42kg)(9.8m/s2)=4.9N Vertical displacement=(3000ft)(1mi/5280ft)(1609m/mi)=914m work=force*displacement Difference in work=(4.9N)(914m)=4497.6J So by choosing the boots I expended about an extra 4500 Joules (about 1070 calories) of energy (but I estimate that in reality It was probably closer to double that). However as we climbed further the trail became covered in snow and ice, making it incredibly wet and slippery, so without the boots I likely would have fallen off the the mountain and gotten frostbite on my feet. In the end think 4500J is a fair tradeoff for not dying.
  39. 1 point
    Throughout the age of cyber technology...one thing has always been a menace to our electronic productivity. There is only one force that can disturb the power of the internet. That force manifests itself as hacking. Ever since computers were available, people (with their natural evil tendencies) wanted to steal others' information. And so they did. A recent hack on Adobe could possibly be the largest ever. 152 Million Adobe accounts were discovered by the security firm LastPass to be compromised by hackers. That's 152 million credit cards...now at the hands of a smart computer user. Although the information has been restored quickly, some hackers have been more lucky. In July of this year, four men successfully hacked into the NASDAQ, among other megacorporations like Citibank, PNC Bank, Heartland Payment Systems, 7-Eleven, and JCPenney. Stealing credit card informatin along the way, these four men "owned" the NASDAQ while they had control over one of the world's largest financial database. I've had a personal encounter with hacking on this website. An anonymous user has breached my account and has recently posted a blog post... Some people want to watch the world burn.
  40. 1 point
    The average aircraft will usually suck up a couple thousand feet in order to stop. The average single piston engine aircraft will take less, and a 747 will take much more (>5000ft). This creates a problem. Aircraft have insane amounts of momentum upon touchdown, and pavement isn't cheap. In addition, we can't have "mobile" airports for military use - so how are we able to deploy combat ready aircraft to anywhere in the world within a matter of hours? Well, we made mobile airports. And, they float! The aircraft carrier was first used in 1920. Essentially, it was a floating street where some aircraft landed, and others careened into the ocean, killing their pilots. There was no effective and safe way to stop aircraft on such a small distance. As of 2013, things have changed. The modern aircraft carrier is a small metropolis, with crews of more than 2,000 sailors. The technology has improved to a point where we're able to launch and recover 90 aircraft on the same ship. But how do we do it? Simple - Hydraulics! Laid across the aircraft carrier's deck are four wires. When an aircraft, like the F/A-18 in the video below, hits the deck, the aircraft "catches" one of those wires on a hook attached to the fuselage of the plane. The wire then rapidly sends kinetic energy of the aircraft to "hydraulic dumping systems" that, in simple terms, tug on the aircraft until it's stopped. It's like a ship with massive, hydraulically-backed rubber bands. But landing is only half of the story. How does the F/A-18 launch from the carrier? Sure, it could take off like a conventional airplane, but the runway is far too short! The aircraft would simply fall off the deck. *insert splashing noise here* We needed some sort of "catapult" to get the aircraft moving fast enough so that the wings could produce more lift than the aircraft's weight. So, we used what we were experts in - Steam! By pressurizing a tank to very high PSIs, that potential energy is released, dragging the aircraft by yet another hook across the deck with a final velocity of anywhere between 120-150 Knots. These catapults will soon be replaced by electromagnets, that use electric currents to create strong magnetic fields to propel the aircraft into the air. These systems are far less expensive than conventional steam catapults.
  41. 1 point
    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!
  42. 1 point
    In many of our video games and even in real life we sometimes come into contact with a hunting rifle or sniper rifle. For some games its just point and shoot and you hit him but for some games and in real life you have to compensate for the drop of the bullet. But did you also know that, that bullet you just shot and the case of that bullet as it flies out are hitting the ground at the same time? But back to the drop of the bullet when you fire. When you fire really any gun you have to aim a bit up from your target depending on the distance you are at. Gravity pulls the bullet down even if it might seem that it would take awhile as the bullet comes out of the gun gravity is acting on it and the bullet is being dragged down but slower that other objects because of the speed it is at. So next time you go hunting and you think that you are going to get the animal right in the sweet spot try aiming a little higher then where you want it to go, then it might be right on. But to come back to something, the drop of the bullet and the shell of the bullet. These two things drop and hit the ground at the same time. As you shoot the bullet goes flying off at high speeds, but when you pull the bolt back on the rifle and the case flies out and hits the ground, both parts of the bullet have hit the ground. They are technically experiencing the same thing its just the bullet shot is experiencing it over a greater distance with a greater speed.
  43. 1 point
    First let me warn you that I'm barely scratching at the surface of consciousness and the scientists still have a lot to learn. When you search this there seems to be two theories one that consciousness is similar to computers the other that consciousness revolves around the unity of different worlds and the reality as we see it is only an illusion. If you want to see a short clip of the physics of consciousness you can watch this: This only tells part of they story and other you tube videos can go on for a couple hours trying to explain consciousness. But one of the main points it brings up is that there is more in this world than by our human senses we can detect. Our bodies are made up of several worlds the one we see and can comprehend, the world of our cells and even smaller the world of the atoms that make up us. The world is made up of waves and somehow the world of intentions can change what goes on. One of the experiments that proved how your thoughts can change the way something turns out is an experimental machine that randomly generates coins of either 1's or 0's. They would tell people to try to count more ones than zeros and according to their results the number they thought about whether it was more ones than zeros or whatever would relate to the number of coins that the coin generator would produce. Another thing they talked about was how their is more than enough energy in the vacuum of space to produce universes. Yet we can't see anything but the vacuum can't be empty because of the continuation of stars being created out of seemingly nothing and the possibility that electrons can be both here and there and nowhere at the same time. Like Mr. Fullerton's cat in the box experimental theory he got from some other scientist trying to explain Quantum Physics. You would theoretically put a cat in the box with a capsule of cyanide that has a 50 percent chance of going off and killing the cat. Yet you couldn't see the cat or shake the box or the capsule would automatically go off. So you would assume the cat was both dead and alive like how with the double slot experiment with electrons you would assume it bounced of the background, went through both slits and also interfered with itself creating the interference pattern. So with the little I know and the information I learned from the video you can learn some interesting facts and concepts about consciousness that you might never have thought about before.
  44. 1 point
    Most people dont realize that there is science through playing a sport. Watching or playing volleyball is a great way to grasp the principles of physics. Understanding physics can be tricky if you just look at the mind boggling equations and such, but by connecting physics to other things, such as volleyball, physics can help you learn in an easier way. Gravity Gravitational force impacts every aspect of volleyball; whether you are serving, passing, or hitting. Gravity will effect every contact with the volleyball. When some one is going to serve, the server uses upward and forward force on the volleyball, while gravity is using a downward force. Because of the downward force of gravity, the volleyball will make it over the net onto the other side. There are different types of serves that can make it harder for the opponent to pass it on the other side. One type of serve is called the jump-float. This particular type of serve has no spin to it, when the player contacts the ball they try to hit the ball with the plam of thier hand without snapping their wrist. When people are performing the jump float serve, they stand back a couple of feet. This is because, the player wants to ensure that the volleyball is cutting through as much air as possible. The longer the volleyball is in the air the more the volleyball is exposed to the air stream. The jump float serve is very similar to a knuckle ball in baseball; it is very hard to time. When being served by a server using the jump float, it seems like the ball is actually floatng in the air. Another type of serve is called the top spin. Top spin serves is quicker than the jump float. When performing a top spin serve the player snaps their wrist, which causes the force on the ball to accelerate quicker to the ground. A top spin serve brings the ball down because the seems on the volleyball are rolling forward.This causes the air velocity to be faster on the top of the ball rather than on the bottom of the ball; this pushes the ball into a downward motion. When a passer is passing a ball an upward and forward force is exerted on to the ball while gravity is pushing the ball down. To ensure that the volleyball will meet at the target spot, the passer will have to follow through with their arms in the direction of the target. When a volleyball player goes up to hit or spike the ball, they try to use as much force as they can so they can get a kill and grant their team a point. When spiking the volleyball the player exerts a downward force on the ball, crushing it to the other side of the net. When spiking the ball, gravity is now working in the players favor. Players dont have to hit the ball as hard because gravitational force is acting on the ball in the same downward direction. Acceleration and Velocity As gravity pulls the ball down, the ball is accelerating. When a player is spiking the volleyball to the other side of the net, the balls velocity has increased showing acceleration .Throughout the game of volleyball, the ball is constantly accelerating and decelerating as well as the player is; this all depends on the forces that the players put on the ball and how quick or low the player moves to get to the ball. A player on one side could pass an easy free ball to the other side, when very quickly a player on the opposing side can spike the ball back with a high amount of force; this is showing the balls acceleration. Through volleyball, you can calculate the velocity of the volleyball. To calculate this you would need to use an equation. In this case, you could use the equation v=d/t. This stands for velocity equals distance divided by time. For example, if the server was behind the service line 25 feet away from the net ad it took 2 seconds for the ball to pass the net to the other side, the velocity would be 12.5 feet per second. The higher the velocity is, the harder it is for the passer on the opposing side to deliever a good three option pass, which is a good thing. More Here is a video explaining even more physics on volleyball. Have fun watching this video and thanks for reading! Just remember that physics isnt a tricky thing to learn if you connect it with cool things like sports!
  45. 1 point
    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
  46. 1 point
    Click below for the Light/Optics Units materials. [ATTACH]686[/ATTACH] [ATTACH]682[/ATTACH]
  47. 1 point
    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.
  48. 1 point
    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
  49. 1 point
    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 batteries. With this technology inside a common electronic device such as an ipod, for the same storage space one could theoretically charge it to full capacity in as little as three seconds, the charge lasting several weeks. although this technology is still far off, one can imagine how mch it would change our lives.
  50. 1 point
    so the other day i let my rabbit have free range of my room for a few hours as i was doing my webassign, and after a while the mouse i was using for my computer stopped working. i checked the plug, and to my confusion it was still plugged in. as i attempted to diagnose the problem i looked below my desk for a moment, finding my rabbit with a mouthful of copper and plastic. tasty. unfortunately he had not only chewed through my mouse cable, but also that of my webcam, among others. i got out my soldering iron and strippers, and as i removed the insulating tubing from each wire i found something interesting. on the mouse wire i removed the insulation to find only the four wires typical of a usb cord, however as i peeled back the insulation on the webcam wire, there was a second layer of braided wire and foil around the center four wires. at first i thought this may be an other data-carrying wire, or possibly a ground, which wouldnt make sense since usb uses very low voltage. i then realized it was just a conducting shell there to block interference with the webcams image quality from outside radio noise using the faraday cage effect. i hypothesized that my mouse didnt have this extra layer because the location of a mouse pointer is somewhat arbitrary on the small scale, so blocking this small ammount of interference would not be cost effective for the company that made it. moral of the story: faraday cages can be pretty useful.


  • Newsletter

    Want to keep up to date with all our latest news and information?
    Sign Up

Terms of Use

The pages of APlusPhysics.com, Physics in Action podcasts, and other online media at this site are made available as a service to physics students, instructors, and others. Their use is encouraged and is free of charge. Teachers who wish to use materials either in a classroom demonstration format or as part of an interactive activity/lesson are granted permission (and encouraged) to do so. Linking to information on this site is allowed and encouraged, but content from APlusPhysics may not be made available elsewhere on the Internet without the author's written permission.

Copyright Notice

APlusPhysics.com, Silly Beagle Productions and Physics In Action materials are copyright protected and the author restricts their use to online usage through a live internet connection. Any downloading of files to other storage devices (hard drives, web servers, school servers, CDs, etc.) with the exception of Physics In Action podcast episodes is prohibited. The use of images, text and animations in other projects (including non-profit endeavors) is also prohibited. Requests for permission to use such material on other projects may be submitted in writing to info@aplusphysics.com. Licensing of the content of APlusPhysics.com for other uses may be considered in the future.

×
×
  • Create New...