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Showing content with the highest reputation since 11/14/2010 in all areas

  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
    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.
  7. 2 points
    Maybe I'll write a post just about cows...*suspense*
  8. 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
  9. 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
  10. 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!
  11. 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).
  12. 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.
  13. 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
  14. 2 points
    11/10 already and all i've read was the title.
  15. 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
  16. 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!
  17. 1 point
    As I was scrolling through Instagram, I came across a post by Nasa that said today, October 14th, 2017, is the 70th anniversary of supersonic flight. Supersonic flight is when something is traveling faster than the speed of sound, which is 343 m/s. Of course for the past 70 years this has only been done by noncommercial planes. Well, Nasa is currently working on making supersonic flight a reality for commercial planes. That would mean that you can travel from New York to Los Angeles in 2 hours. Now it takes over 6 hours. Nasa has been researching shock waves, cruise efficiency, and the effect of sonic booms on the environment. Sonic booms are loud boom sounds caused by the waves of sound. It occurs when an object travels at supersonic speed. If Nasa is able to make this a reality in will revolutionize modern travel.
  18. 1 point
    No, not that 5th dimension. I'm actually here to talk about five-dimensional space, not soul music - but regardless, I hope this piques your interest. Last post, I researched the 4th dimension, and attempted to break it down in a concise, easy-to-understand, yet informative manner. This is pretty much impossible to do, especially throwing a new dimension into the mix; so again, you'll have to look for yourself to get a more comprehensive view. (Known as a 5-cube) Several branches of physics, namely particle and astrophysics, studies and debates whether or not the universe we inhabit is, in some way or another, five-dimensional. Essentially, the 5th dimension is a hypothetical dimension beyond the three spatial dimensions which we know, and the dimension of time brought to us by relativity. Several theories were developed around such a dimension; for example, shortly after the theory of relativity came into fruition, an extension of it emerged concerning the 5th dimension. It was developed over the course of two decades, and was known as the Kaluza-Klein theory. Initially, it unified gravitational forces with electromagnetic forces - then Oskar Klein came along to give this theory a quantum interpretation, stating that this dimension was "rolled up" and microscopic. This "microscopic" view actually corresponds with string theory, which relies on the existence on 11 dimensions. In this view, 7 out of the 11 dimensions would be rolled up and existent only at the subatomic level. Some speculations occur in this respect - one of these being that the graviton, a particle said to carry the force of gravity, may somehow permeate into the 5th dimension or higher. This would supposedly explain why gravitational forces are weaker than the other 3 fundamental forces - strong nuclear, weak nuclear, and electromagnetic. So how should we view this 5th dimension? A "holographic principle" was put forward by Dutch theoretical physicist Gerard 't Hooft, which states that a dimension can be viewed as curvature in a spacetime with one fewer dimension. For example, a hologram is a 3-D picture on a 2-D surface, giving it the visible curvature that we all notice. Likewise, the fourth dimension would be the curvature path of a test particle in three-dimensional space. 't Hooft also speculated the 5th dimension to be the spacetime fabric - that continuum which can be distorted by large masses/gravity. A hypersphere in five-dimensional space, the volume enclosed by the set of all points in 5-space equidistant from a central point, is given by the equation , where r is that distance from the center point. (I just added this for the people like me who want to see some tangible math to break up the crazy theoretical stuff.) That's about all I have, so remember to research further if you're interested - I can't do this stuff justice!
  19. 1 point
    "Mathematics, rightly viewed, possesses not only truth, but supreme beauty — a beauty cold and austere, without the gorgeous trappings of painting or music." —Betrand Russell Physics is, in essence, applied mathematics. It's how math applies to life, and the results thereof. And math is... beauty? That's not how one would usually think. However, there is a certain beauty to math and how everything resolves itself when it is applied. The way tree growth and snowflakes resemble fractals, light waves follow the simplicity of a sine curve, a top wobbles back and forth, light bends around a magnifying glass - heck, we learned some of these last year in physics B. But while analyzing the theory behind it, how many of us stepped back to think of the beauty? However I explain it, watching it makes it better.
  20. 1 point
    I see that you like to disc golf? that sounds very interesting to Shabba. Shabba would like to hear the physics behind, how you say, disc golf.
  21. 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.
  22. 1 point
    I am very impressed by your independent study! You have prepared yourself well for your intended major.
  23. 1 point
    Even after understanding the physics of it, Im probably still awful at playing it!
  24. 1 point
    Wow, nice job. Don't forget the negative sign for gravitational PE, Ug= -GMm/r
  25. 1 point
    due to my procrastinativity, i now have to due all ten posts in one night. its getting quite bland. i feel like talking about computer screens, as it is what i have been staring at for the last hour. so i shall. most screens are lcd, or liquid crystal display. i dont really know why crystals are involved, but it makes me sound like i know what im talking about. in an lcd screen, there are hundreds and sometimes thousands of small boxes called pixels that make up an image. Typically, each pixel is composed of three sections, each for one of three of the primary colors. as you probably know, the primary colors are all you need to make any color out there, however there are two different sets of primary colors, to be used with different applications. why? one set is the additive primarys and the other is the subtractive primarys. in second grade art class, the primary colors were red, blue, and yellow; the subtractive primarys. these were used because paints and inks and such use subtractive color blending, meaning they absorb, or subtract out some wavelengths of light that hit them, the rest reflecting into your eyes as a specific color. each color subtracts a different wavelength from the original white and reflects only one wavelength, and by blending them you can subtract just the right amount of each from white for your desired color. for computer screens, however, (also projectors, ipods, anything that emits light to create colors), the additive primaries are used, being red, blue, and green, one for each section of pixel in an lcd screen. these are different because with a pixel, colors are created additively, or shining just the right ammount of each wavelength from the different color sections, adding just the right ammount of each for your intended color. for example, you see yellow on a screen because red and green light is hitting your retina, activating some green receptors and some red receptors, which your brain recognises as yellow because it is close to the middle of these two wavelengths. also, white light can only be made with additive primaries, as you add all the wavelengths while black light can only be made by subtractive primaries, when you subtract all the wavelenghts from the original white. doesnt this mean computer screens cant create black? they do so by not adding any color, relying on the background of the screen to absorb light that hits it, so actually, every pixel displaying this text is actually every pixel thats not displaying this text. mind. blown.

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