FizziksGuy

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Everything posted by FizziksGuy

  1. Yup, great catch! Updating...
  2. Absolutely beautiful. And you put that first video together? Great dramatic musical selection to go with it!!!
  3. That is a FANTASTIC question, and to answer it, we need to understand that by accelerating at the top position, we're no longer maintaining a circular orbit, but setting up an elliptical orbit. If we increase the speed of the satellite in that top position, we've increased the kinetic energy of the satellite at that position. But a more complete orbital analysis must take into account gravitational potential energy. By increasing the kinetic energy at the top position, we'll trade that speed off for gravitational potential energy at the bottom position. The following web page goes into more detail (https://www.physicsforums.com/threads/orbital-speed-faster-is-closer.733175/), but the best way I've found to get a good feel for orbital mechanics is to play games. As mentioned on the thread above, Orbiter is a free game that will give you a good feel for it, but Kerbal Space Program is a lot more fun in my opinion (though it's not free). :-)
  4. Hi Scott, The PDF book itself isn't printable due to licensing restrictions, however, you can print out all the original worksheets here: http://www.aplusphysics.com/courses/regents/worksheets/ws_index.html. The answer key is only available in electronic form.
  5. I'm assuming you're attempting to use v=d/t and coming up with L/t. Recall, though, that this formula gives you AVERAGE velocity. V_f is equal to 2*average velocity under constant acceleration, which you can provide by: v_0=0 v=? d=L a t=t Solve vf^2=v_0^2+2ad to get v_f=Sqrt(2aL) Solve d=v_o*t+.5*a*t^2 to get a=2L/t^2 Combine those two equations to eliminate a and solve for vf to show vf=Sqrt(4L^2/t^2)=2L/t
  6. I'm not sure I completely understand the question, but if I attempt to read between the lines, you're wondering why this isn't the same as a block sliding down a ramp. Recall for the box sliding down a ramp scenario, we're setting the motion of the box along the x-axis and 'tipping' our axes to line up with that motion. In this case, although it looks like a box on the ramp, the car is actually moving into or out of the page, not sliding down the ramp. The direction of its motion is centripetal as it goes around the curve, or directly to the right (along the x-axis)... so we don't tilt our axis in this problem. As the car's motion is along the positive axis, directly horizontal, that remains our 'reference' axis.
  7. I'm hoping you get some good news too...
  8. Fantastic application of physics in soooo many ways. I'm always floored by aircraft carriers and how they're able to maintain such stability. Big ships are totally cool!
  9. Not long ago I acquired a Playstation VR (PSVR) which I set up in my basement office, and was asked to evaluate the system for potential educational applications. Beyond that, my scope was wide open, though I was provided the opportunity to sample a variety of games on the system to get a feel for the potential of the system. What follows are some general ramblings and thoughts about the system. The Hardware Playstation VR Headset and Camera The tested system included a Playstation Pro console, a PSVR Launch Bundle (headset, two move controllers, camera, and appropriate cables), and external Playstation Gold headphones in place of the standard earbuds. Included software included a Demo Disk, and Playstation VR Worlds Disk, and I utilized a store credit to try out several system games of my choosing. First Impressions Initially, I was somewhat disappointed in the resolution of the headset. Though I had been forewarned that resolution wouldn’t be as sharp as an HD monitor, I was initially taken aback at the poor quality of the Playstation’s Main Menu rendering and the level of color aliasing I was seeing, especially in white text. With 20/20 vision following Laser PRK corrective eye surgery nearly 20 years ago, this was a bit of a shock to the system that provided some initial disappointment. I quickly found out, however, that this effect is especially bad in the Playstation Main Menu, and is not indicative of the system’s performance as a whole. Further, with some time in the system, I found that placing the headset a touch lower over my nose (lower PSVR screens, higher eyes) improved sharpness considerably. Still, though, after nearly 20 hours using the system, I would say the resolution of the system is adequate, but with substantial room for improvement in the future. From an immersion standpoint, however, I was blown away. After about two minutes in my first simulation, the VR Worlds “Ocean Descent” program, I was having a blast descending in a shark cage through the ocean. It’s hard to convey just how immersive it is, as I swiveled my head back and forth, leaned forward over the bars of the cage to look down, and eventually jumped through my seat when a shark ran into the cage. Further, the resolution concern quickly evaporates in actual gameplay. From a comfort standpoint, I found the headband that holds the PSVR a bit tight, but fairly well balanced. You don’t feel as though there is a weight on your head, and the over-the-ear headphones are a huge improvement over the included earbuds, though it is a bit of a trick to figure out how to put the PSVR headset on, followed by the earmuff-like headphones. The cabling is a bit tricky to figure out while you are looking into the VR headset, but after a couple tries, you get a system down pretty easily. The only lingering concern I had with the headset involved rubber nose flaps that push against the outside of your nose. Try as I might, I couldn’t find a way to make them comfortable, and they pushed just enough on the outside of my nose that breathing was slightly impeded. Just recently I finally decided to cut them off altogether with scissors, and am absolutely thrilled with the improvement in comfort. One of the primary concerns with VR systems is the potential for nausea / motion sickness. VR systems are so immersive that they trick your brain into thinking it’s moving, which may be in opposition to your other senses, leading to motion sickness. I didn’t have any trouble with the Ocean Descent demo, though the first time I tried the “London Heist” demo, also on the Playstation VR Worlds Disk, a car chase scene had me feeling a little bit ‘off.’ I never became overly ill, but I was also careful to discontinue use of the PSVR anytime I began to feel the least bit queasy. Other activities that led to queasiness included Driveclub VR (regular driving was OK, but spinning out upon collision forced me to quit immediately), and a few circumstances when the dog came between me and the camera during a game, in which tracking was lost and the PSVR displayed weird motions that weren’t accompanied by my head movements. It has been reported by many that over time the motion sickness effect lessens as your brain becomes accustomed to the VR system. My experience was consistent with these reports. Finally, I found upon removing the nose flaps my breathing improves, I remained cooler during use of the system, and that also appears to have contributed to reduced nausea. I should note here that another ‘trick’ to improving comfort levels is to have a fan blowing on your face while using the PSVR system. I tried this recently as well and found it a nice enhancement. Immersion The immersion level in PSVR, from my standpoint, is amazing. After you get over the “wow” factor in a game or simulation, you quickly begin to feel as if you are really there. The surround sound headphones coupled with the extremely smooth tracking truly give you the feeling of being there. The PSVR does appear to have an issue with drift over time, where the center focus area of your screen can lead you to looking off-center. A button on the controller can be held to re-center the system, an act that becomes second nature over time, and at regular intervals I find myself closing my eyes and relaxing for a second while pressing the button, then re-opening my eyes to a fully re-centered view. My most-recent PSVR expedition found me attempting the first AAA game release, Resident Evil 7: Biohazard, completely in VR. To begin with, the shortcomings of the graphics system previously detailed is nearly non-existent in this game, which leads me to believe many of my graphics concerns can be mitigated by software. I should also note that I’m not typically a horror fan, though I do recall playing a Resident Evil game on a Playstation some 20-ish years ago. To say this game induced an emotional response is an extreme understatement. Though there are several “jump scares” throughout the game, this title doesn’t rely on them, and instead does a fantastic job of creating an environment of suspense and foreboding using the PSVR hardware. You truly feel like you’re there, and I’m not ashamed to admit I nearly had to purchase new drawers when I was playing the game one evening and the dog jumped on my lap at an inopportune time. With the goal of finishing a report on immersion by the end of February, I wanted to work through this entire game by mid-February, which totaled roughly 10 hours of in-game time. Though I experienced one technical hiccup which required a reboot of the entire system, I completed the adventure yesterday. I could continue talking about my thoughts on immersion, but I believe my habits around using the PSVR to play RE7 tell it all… after the first night, I told my wife I couldn’t play this after the kids went to bed… it was too creepy. Instead I tried to sneak in an hour after dinner, or on weekend afternoons. The immersion level is just that high. Implications Following this trial (which I’ll be continuing for some time), I’m now a believer that there are tremendous opportunities for the use of VR in education. Though I don’t see this as a popular “in-class” tool in standard high school settings due to the cost/complexity/infrastructure required, I do think as an individual tool some amazing things could be accomplished. Imagine a history class in which students don’t just read about the Battle of Gettysburg, but actually get to “live it” from various perspectives. Envision a biology lesson in which you are miniaturized and travel through the bloodstream to various organs, seeing the operation of the heart from the inside (remember Inner Space, anyone?) Or a virtual dissection for biology and anatomy classes. Picture the ability to explore a nuclear reactor from the inside, with the ability to zoom in and ‘view’ the actual chemical and physical reactions as they occur, or traveling through a circuit as an electron. Imagine viewing a surgical procedure from the standpoint of the operating physician! You could explore the universe at will, or dive into the geology of the Earth from the inside. The possibilities are limitless, though I imagine tools to build such simulations must evolve to the point that content instructors have content creation and distribution tools that will make the learning curve for such projects reasonably accessible. I haven’t investigated this in-depth, but I would believe that such accessibility is a ways off, but getting closer every day. Though not quite as immersive, I can also envision the use of this technology for distance learning courses, though there are challenges for this as well. I imagine streaming or recording classes in a VR-friendly format may not be way off, but appropriate application will take significant further thought. “Sitting in” on an MIT lecture and demonstration may be possible, but is it a significantly more engaging experience than a two-dimensional video cast of the course? Would the VR technology and headset make note-taking and student work while participating in the class too restrictive? What tools and interactivity would make this a positive leap in learning vs. a play area where the complexity overcomes the educational benefits? It is extremely early, but I look forward to seeing how such amazing technology is utilized for purposes beyond just standard gaming. And in the meantime, I’m having a blast not only trying out the technology, but envisioning potential applications for the future. Please let me know in the comments what potential opportunities you can envision for virtual reality in education!
  10. The post LaTeX for High School Math and Science appeared first on Physics In Flux.
  11. You may have noticed it’s been a LONG time since I’ve updated this physics education blog. More likely you haven’t noticed, because it’s been a LONG time since I’ve updated this blog. This hasn’t been due to a lack of topics to write about, but rather, it’s been a conscious choice to plow full steam ahead on a project that began in June of 2013 and that I’m thrilled to announce is now available, The AP Physics C Companion: Mechanics. But first, some background. Traditional AP Physics C As a teacher of calculus based physics (AP Physics C – Mechanics and AP Physics C – Electricity and Magnetism), I’m faced with a very unique challenge in those courses. I typically enjoy classes of bright, motivated students who are preparing for careers in engineering, science, medicine, and other technically challenging fields. And I love teaching the content of these courses — the level of technical challenge keeps me motivated, and I love the highly mathematical nature of the course. In teaching the class, however, what I found is a very aggressive schedule to fit both courses into the school year, and my students are co-enrolled in calculus (which means they typically need to solve calculus problems in physics before they’ve been introduced to the calculus in their mathematics classes). Further, teaching in a traditional style, I found that most topics fit fairly well into our 42-minute periods. Students come in to class, begin with a warm-up question tied to the previous day’s topic, which we spend a few minutes reviewing, then I have time to present a single topic with an example or two each day. If we don’t take any breaks, and throw in a quiz or test every couple weeks, as well as some fairly straightforward lab activities, we JUST barely get through all of our material in time for the May AP exams. What I especially enjoy about this class and this method of teaching, however, is the face-to-face time with the kids during the daily lessons. Class sizes for AP Physics C is typically small enough that we have a very informal style that is warm and inviting, yet challenging for all. The students enjoy the class, taking notes from their seats each day, and doing book problems and old AP problems for homework in the evenings. And our AP scores each year are solid. In September of 2011, however, I decided to try something different. I wanted to get away from the teacher-centric model, as I realized that I was the hardest working person in the classroom. This contrasted with the best teaching advice I ever received, when our assistant principal and my mentor explained that I should strive to “Look like the laziest teacher in the building while the students are in the classroom, and the hardest working teacher in the building the moment they leave.” What he meant was students should be doing the work in the classroom, especially as I continuously espoused my belief that physics is something you do, not something you know. Although the students were doing OK in their passive roles as notetakers, this was a credit to the strength of these students, not my teaching. A New AP Physics C Methodology Instead, I began to imagine a classroom in which students directed their own learning, building lifelong learning skills that would serve them well outside the narrow discipline of future physics courses. With the blessings of our administration, I undertook a giant experiment in the classroom. We went through the year with the goal of having zero teacher lectures. Instead, I completely “flipped” the classroom. Students were expected to watch video mini-lessons on topics outside of class, as well as read the textbook and take notes, saving classroom time for group discussions and problem solving, hands-on lab activities, and deeper dives into topics of interest. I ended up going back to traditional lectures on two topics — Gauss’s Law and the Biot-Savart Law, but for the most part the class ran independently. I built up “packets” of assignments, practice problems, labs and activities for each unit, and students worked at their own pace (within reason) through each unit. Unit exams were given when students said they were ready, with multiple re-take opportunities. This evolved into a self-paced course, and at the end of the year, I found AP scores were significantly higher than in past years, which in retrospect shouldn’t have been surprising. Teaching in this more hands-off manner is very uncomfortable, however. I “feel” like I’m doing a great job when I’m working hard, presenting great lectures, and interacting with the students. Stepping back and watching the students work, only getting involved to ask the occasional question or provide some basic clarification and support is extremely challenging. Given the results, though, I tried it again the following year. Same result! These classes were regularly polled for feedback on the course. General observations were that many students felt more intimidated and lost at the beginning of the course. As well, there were several points throughout the year in which the students felt quite frustrated. Polls at the end of the year, however, indicated students felt very confident in their self-teaching abilities, their ability to work through challenges they initially thought impossible, and their comfort level with their preparation for future studies. The most common opportunity they identified for improvement — learning how to read the textbook. In an effort to address this, I’ve implemented a variety of changes in my classroom. First off, we take some time at the beginning of the year and again after mid-terms to talk about and practice strategies for reading a technical text. We also take some time to talk about how to actively use the video lessons and example problems so that study time is efficient and productive. The AP Physics C Companion: Mechanics Finally, I started work on a “companion” text to the AP Physics C curriculum, focused on distilling down the key points from the text and illustrating them with a variety of applications. Not really a review book (though it could be used in that sense), but rather a cleaned-up version of instructor notes for the course that could be applicable to any calculus-based mechanics course. A large focus of the book is trading off technical complexity for illustrated application of concepts, including justifications for problem solving steps in the problems themselves, and well-documented problem solutions. I’ve been using the notes and draft chapters of this book for several years in my classes, which has allowed me a “test run” of various sections and the opportunity to see what works with students, and what needs further revision. The final result, I’m excited to say, is now available as “The AP Physics C Companion: Mechanics.” It will first be available in black and white print editions from APlusPhysics.com and Amazon, as well as a full-color PDF edition on APlusPhysics.com. Shortly thereafter, print editions (both color and black and white) will be available from any retailer, including Amazon and Barnes and Noble. Finally, bulk purchases will be available directly from sales@sillybeagle.com (Silly Beagle Productions) at substantial discounts. Where’s the E&M Book? I’ve already been asked repeatedly if there’s an E&M version planned. The answer is rather convoluted, however. The E&M version is half done — the draft is complete as part of my class work and has been for more than a year. I haven’t typeset it yet, however (probably a 6-12 month project), or worked on the graphics for a few reasons. First, it is a huge investment of time to do so, which puts other projects on the back burner. Second, the market for such a book could be pretty small. As only 27,000 students took the AP Physics C: E&M exam last year, that’s a very limited market to cater to. Though the book would be appropriate for an introductory calculus-based E&M course, a very significant portion of students taking the E&M exam would have to purchase and use the book in order to recuperate the costs involved in putting out the book (which are substantial). As most any science author will tell you, there’s not much profit to be made in writing these types of books, and margins are mighty slim. It’s a labor of love because you want to help students (yours and others). I’m already pushing the limits of ‘wise decisions’ in marketing a book to the AP-C Mechanics market (53K test takers last year), and hoping it at least breaks even. Before making any commitments to an E&M version, I want to obtain feedback from the mechanics version — are students and instructors finding it helpful, what is a reasonable percentage of the market to anticipate, would it at least break even, and how is the new format received (fewer pages, larger format and type, color vs. B&W, etc.) Given all that, I imagine it’s probably likely at some point I’ll get to work on it (after every book I tend to think I’m done, then eventually change my mind and start on another one). However, it feels good to “fool myself” for awhile and pretend I’m done while I work on updating the APlusPhysics site, continue work on instructional videos, and perhaps get to bed a little earlier in the evenings. For now, however, I’m excited to announce the release of The AP Physics C Companion: Mechanics. Hope you enjoy it as much as I enjoyed putting it together! *AP and Advanced Placement Program are registered trademarks of the College Board, which does not sponsor or endorse this product. The post New AP Physics C Mechanics Book Release appeared first on Physics In Flux.
  12. View File The AP Physics C Companion - Mechanics The AP* Physics C Companion - Mechanics is an easy-to-read companion to the AP Physics C: Mechanics curriculum, featuring 350 sample problems with fully worked-out solutions. The AP Physics C Companion: Mechanics covers all major topics of the AP Physics C Mechanics course, including fundamentals of calculus, kinematics, dynamics, work, energy, momentum, rotation, oscillations, and gravity. The AP Physics C Companion is not a textbook replacement nor is it a strict test-prep guide. It is a short, sweet roadmap to calculus-based physics courses such as AP Physics C: Mechanics and University Physics I, invaluable not just during test prep time, but throughout the entire course. The book lays out basic physics principles as quickly and clearly as possible, then demonstrates their application with hundreds of example problems solved in detail. Written by a physics teacher, The AP Physics C Companion correlates directly with the APlusPhysics.com website, where you will find free video mini-lessonsexplaining fundamental concepts, detailed study guides, a question and answer discussion board, and most importantly, a meeting place where you can interact with other students from around the world. This is a license for a digital download of the PDF version for use by one person only on up to five electronic devices. This document may not be printed, edited, re-distributed, re-sold, or licensed to any other user. Once the file has been downloaded no refunds will be given. Submitter FizziksGuy Submitted 02/14/2017 Category Books  
  13. Version 1.0.1

    The AP* Physics C Companion - Mechanics is an easy-to-read companion to the AP Physics C: Mechanics curriculum, featuring 350 sample problems with fully worked-out solutions. The AP Physics C Companion: Mechanics covers all major topics of the AP Physics C Mechanics course, including fundamentals of calculus, kinematics, dynamics, work, energy, momentum, rotation, oscillations, and gravity. The AP Physics C Companion is not a textbook replacement nor is it a strict test-prep guide. It is a short, sweet roadmap to calculus-based physics courses such as AP Physics C: Mechanics and University Physics I, invaluable not just during test prep time, but throughout the entire course. The book lays out basic physics principles as quickly and clearly as possible, then demonstrates their application with hundreds of example problems solved in detail. Written by a physics teacher, The AP Physics C Companion correlates directly with the APlusPhysics.com website, where you will find free video mini-lessonsexplaining fundamental concepts, detailed study guides, a question and answer discussion board, and most importantly, a meeting place where you can interact with other students from around the world. This is a license for a digital download of the PDF version for use by one person only on up to five electronic devices. This document may not be printed, edited, re-distributed, re-sold, or licensed to any other user. Once the file has been downloaded no refunds will be given.

    $10.00

  14. I also have a "microelectronics in high school" mini-unit that covers the basics of not only transistor functionality, but device physics, chip design, and manufacturing: http://www.aplusphysics.com/educators/STEP.html
  15. Name: Mechanical Universe: The Millikan Experiment (12) Category: Electricity & Magnetism Date Added: 2017-02-07 Submitter: FizziksGuy Episode 12. The Millikan Experiment: A dramatic recreation of Millikan's classic oil-drop experiment to determine the charge of a single electron.“The Mechanical Universe,” is a critically-acclaimed series of 52 thirty-minute videos covering the basic topics of an introductory university physics course.Each program in the series opens and closes with Caltech Professor David Goodstein providing philosophical, historical and often humorous insight into the subject at hand while lecturing to his freshman physics class. The series contains hundreds of computer animation segments, created by Dr. James F. Blinn, as the primary tool of instruction. Dynamic location footage and historical re-creations are also used to stress the fact that science is a human endeavor. The series was originally produced as a broadcast telecourse in 1985 by Caltech and Intelecom, Inc. with program funding from the Annenberg/CPB Project.The online version of the series is sponsored by the Information Science and Technology initiative at Caltech. http://ist.caltech.edu©1985 California Institute of Technology, The Corporation for Community College Television, and The Annenberg/CPB Project Mechanical Universe: The Millikan Experiment (12)
  16. Episode 12. The Millikan Experiment: A dramatic recreation of Millikan's classic oil-drop experiment to determine the charge of a single electron.“The Mechanical Universe,” is a critically-acclaimed series of 52 thirty-minute videos covering the basic topics of an introductory university physics course.Each program in the series opens and closes with Caltech Professor David Goodstein providing philosophical, historical and often humorous insight into the subject at hand while lecturing to his freshman physics class. The series contains hundreds of computer animation segments, created by Dr. James F. Blinn, as the primary tool of instruction. Dynamic location footage and historical re-creations are also used to stress the fact that science is a human endeavor. The series was originally produced as a broadcast telecourse in 1985 by Caltech and Intelecom, Inc. with program funding from the Annenberg/CPB Project.The online version of the series is sponsored by the Information Science and Technology initiative at Caltech. http://ist.caltech.edu©1985 California Institute of Technology, The Corporation for Community College Television, and The Annenberg/CPB Project
  17. Yikes. Hope you're doing OK.
  18. And keeps your fries tasty!
  19. File Name: WS: Momentum and Motion File Submitter: FizziksGuy File Submitted: 19 Apr 2013 File Category: Momentum & Impulse Problem set combining conservation of momentum, projectile motion, and friction.
  20. Good Afternoon, This is designed as a problem to compliment the Regents and Honors programs of study with this website (hence its location in the Regents and Honors folder), in which the coefficient of friction for wood on wood is a given and is designed to be looked up in a reference table (see link below). And yes, the first box would experience friction, however, based on the problem statement, you know the velocity of the first block as it contacts the second block, therefore there's no need to calculate a reduction in velocity prior to impact. Then, following the impact, and knowing the coefficient of kinetic friction of wood on wood, you can solve for the horizontal launch velocity using Newton's 2nd Law, at which point this becomes a projectile problem. Links to reference table with friction information: http://www.aplusphysics.com/courses/honors/dynamics/friction.html I would agree, however, that if you didn't know the coefficient of friction, you'd be stuck.
  21. I think it's safe to say you've never made waffles and pancakes? One is definitely faster, but it's not the waffles...
  22. Hi Gio. APlusPhysics is just a single person, me, so that's pretty easy to answer. They are on my to-do list, but are at best a month or two away. Note that most of this material is covered to at least some depth in the "Honors" physics video series. Hope that helps! -Dan
  23. Spent TONS of times in clean rooms, most of which at a cleanliness level thousands of times cleaner than surgical suites. There is a TON of money and engineering spent on creating cleanrooms -- fantastic career opportunities!
  24. And since it's about baby squats... gotta start 'em young!