FizziksGuy

Emily and Kelsey's potato gun project, AP-C Physics 2012

A short video of a student project to build a working Rubens' Tube.

Check out this picture of diffraction in the Finger Lakes region of upstate NY from Google Maps! [ATTACH=CONFIG]432[/ATTACH]

Check out this shot from Google Maps demonstrating diffraction in the Finger Lakes region! Source

Check out this shot from Google Maps demonstrating diffraction in the Finger Lakes region! http://feeds.feedburner.com/~r/PhysicsInFlux/~4/JkF553E-K3g Source

Check out the homework help forum post here. Best wishes! :banghead)

Hi! It depends on what you mean by N35degreesE. If you mean 35 degrees north of east, I would find Ax as 4.0cos(35) = 3.28 km. If you mean 35 degrees east of north, the angle with the horizontal would be 55 degrees. Based on what you're telling me, I imagine N35degreesE is being used to represent 35 degrees east of north. Therefore, this would look similar to the diagram below: [ATTACH=CONFIG]431[/ATTACH] Does this help with your problem? Make it a great day! Dan

Good Afternoon, Yes, you could say the atoms have an electron charge of -1C, the protons have a charge of +1C, therefore there is no net charge. A piece of metal can have a net charge on its own. For example, an atom (ion) with 4 electrons and 3 protons has a net charge of -1.6x10^-19 C. Net charge and potential difference are quite different critters. What the electrons are doing is actually a very complicated question. Electrons around an atom are represented as being in a "cloud" of probable locations. Strangely enough, in a short enough time interval, that electron can actually be in more than one place at a time! As you get into the physics of the very small and very fast, life gets weird in a hurry. Best atom for you to start with would be hydrogen. If I can, I'll refer you to the Models of the Atom tutorial. If you start with hydrogen, it can pick up an extra electron to become a hydrogen ion (-1e), or it can lose its electron to become a hydrogen ion (+1e). If it were to lose its proton, it wouldn't be hydrogen anymore. Yes, you can have a hydrogen atom with no electrons. Lose the proton, though, and by definition it's no longer hydrogen. This may also help you in your quest to understand electricity: http://www.aplusphysics.com/courses/regents/electricity/regents_electric_charges.html Good luck!

Wow, great questions ElyxR! I love it when folks want to genuinely UNDERSTAND, not just learn enough to pass the test. And it sounds like you're doing pretty well so far -- and I agree, voltage / potential difference is one of the hardest parts of electricity to truly understand -- I certainly didn't "get it" my first, or even second, time through. And I'm still learning more each time I teach it. So, let's get down to your questions. The charge on a single electron is -1.6x10^-19 C, or, put another way, 6.24x10^18 electrons would give you -1 coulomb of charge. Correct. That piece of metal on your desk, yes, you could say you have 1C worth of electrons, although it's not a very meaningful statement. For charge to be useful, you're usually looking at NET charge. For example, if you have an electron and a proton, with charges of -1e and +1e, respectively, overall you have a net 0 charge. When things get interesting is when you have an imbalance of charge... extra electrons (negative charge), or lack of electrons (positive charge). And yes, the electron has that charge even though it is not in a situation of potential difference with another particle somewhere else. Charge is a fundamental property of that electron. You can't have an electron without having a charge of -1e. Hope that gets you started! (by the way, scientists later learned that you can actually have charges smaller than 1e, when you start getting into sub-atomic particles such as quarks -- you can learn more about it by watching the "Standard Model" video, but for your current goals and all practical purposes, it really doesn't make a difference at this point!) Make it a great day!

A great video to review the Standard Model.

It's funny that this "secret reactor" seems to be such a big deal in the news recently. We used this regularly in my previous life as a microelectronic engineer at Kodak, and it certainly wasn't a secret!

As we close in on the end of our year in high school physics, I thought it'd be helpful to myself (and perhaps to others) to put together a compendium of some of the best Regents/Honors Physics resources to assist students in preparing for their final exams. Without further ado, and in no particular order: [ATTACH=CONFIG]417[/ATTACH]APlusPhysics: Dan Fullerton's (my) site to assist students and educators specifically around the NY Regents Physics curriculum, which has been expanding and generalizing to curricula outside the state as well. The Regents Physics section of the site, however, is by far the strongest and most complete. This site includes online tutorials covering the entire Regents Physics course, interactive quizzes pulling from a database of hundreds of old Regents Physics Exam questions, video tutorials of every major topic covered by the exam, and is also tied in quite closely with the Regents Physics Essentials review book. In addition, every Regents Physics questions from the past 16 exams has been pulled into worksheets by topic to allow for highly directed practice. ScienceWithMrNoon: Brendan Noon's physics site has a wide variety of great content, including topic-based interactive quizzes and tons of great physics videos. His course calendar, as well, is loaded with tons of great resources by topic! St. Mary's Physics: Tony Mangiacapre's site, full of great lessons and interactive simulations across the entire Regents Physics curriculum. I'm especially fond of the Photoelectric Effect simulation -- makes for a great computer-based lab activity! This site is also closely linked with Tony's 123physics.com, featuring more than 1300 Regents Physics Exam questions broken down by topic for students to practice, as well as more great videos. RegentsPrep.org: The Oswego City School District (with Dr. Tom Altman) has pulled together a strong collection of resources broken into Explanations, Demos, Labs, and Quizzes to assist students and educators in preparing for the Regents Physics exam. Altman Science: The charismatic Dr. Tom Altman provides real-life demonstrations and explanations of physics concepts in action as part of the High School Physics Project. Further, he's broken down a number of old Regents Exams and walked through solutions to each and every question in video format, page by page. In addition, his laser videos are "wicked cool" as well! Past Regents Exams: The name says it all -- an amazing archive of old Regents Physics exams! Regents Physics Essentials: I'd feel negligent if I didn't point out the Regents Physics Essentials review book I put together at student urging a few years back. *There are a number of great review books to help students get ready for the exam, but this book takes a slightly different twist by providing students a straightforward, clear explanation of the fundamental concepts and more than 500 sample questions with fully-worked out solutions directly integrated in the text. As stated by my physics teaching cohort in crime at our high school, "the best review book is the one students will actually use," and this was written to be friendly, fun, and concise. Plus, if students/teachers want extra problems without solutions given, the worksheets are available free online! You can check out the book's free preview on APlusPhysics or use Amazon's "Look Inside" feature!

As we close in on the end of our year in high school physics, I thought it’d be helpful to myself (and perhaps to others) to put together a compendium of some of the best Regents/Honors Physics resources to assist students in preparing for their final exams. Without further ado, and in no particular order: APlusPhysics: Dan Fullerton’s (my) site to assist students and educators specifically around the NY Regents Physics curriculum, which has been expanding and generalizing to curricula outside the state as well. The Regents Physics section of the site, however, is by far the strongest and most complete. This site includes online tutorials covering the entire Regents Physics course, interactive quizzes pulling from a database of hundreds of old Regents Physics Exam questions, video tutorials of every major topic covered by the exam, and is also tied in quite closely with the Regents Physics Essentials review book. In addition, every Regents Physics questions from the past 16 exams has been pulled into worksheets by topic to allow for highly directed practice. ScienceWithMrNoon: Brendan Noon‘s physics site has a wide variety of great content, including topic-based interactive quizzes and tons of great physics videos. His course calendar, as well, is loaded with tons of great resources by topic! St. Mary’s Physics: Tony Mangiacapre‘s site, full of great lessons and interactive simulations across the entire Regents Physics curriculum. I’m especially fond of the Photoelectric Effect simulation — makes for a great computer-based lab activity! This site is also closely linked with Tony’s 123physics.com, featuring more than 1300 Regents Physics Exam questions broken down by topic for students to practice, as well as more great videos. RegentsPrep.org: The Oswego City School District (with Dr. Tom Altman) has pulled together a strong collection of resources broken into Explanations, Demos, Labs, and Quizzes to assist students and educators in preparing for the Regents Physics exam. Altman Science: The charismatic Dr. Tom Altman provides real-life demonstrations and explanations of physics concepts in action as part of the High School Physics Project. Further, he’s broken down a number of old Regents Exams and walked through solutions to each and every question in video format, page by page. In addition, his laser videos are “wicked cool” as well! Past Regents Exams: The name says it all — an amazing archive of old Regents Physics exams! Regents Physics Essentials: I’d feel negligent in my feeble attempts at self-marketing if I didn’t point out the Regents Physics Essentials review book I put together at student urging a few years back. There are a number of great review books to help students get ready for the exam, but this book takes a slightly different twist by providing students a straightforward, clear explanation of the fundamental concepts and more than 500 sample questions with fully-worked out solutions directly integrated in the text. As stated by my physics teaching cohort in crime at our high school, “the best review book is the one students will actually use,” and this was written to be friendly, fun, and concise. Plus, if students/teachers want extra problems without solutions given, the worksheets are available free online! You can check out the book’s free preview on APlusPhysics or use Amazon’s “Look Inside” feature! Source

As we close in on the end of our year in high school physics, I thought it’d be helpful to myself (and perhaps to others) to put together a compendium of some of the best Regents/Honors Physics resources to assist students in preparing for their final exams. Without further ado, and in no particular order: APlusPhysics: Dan Fullerton’s (my) site to assist students and educators specifically around the NY Regents Physics curriculum, which has been expanding and generalizing to curricula outside the state as well. The Regents Physics section of the site, however, is by far the strongest and most complete. This site includes online tutorials covering the entire Regents Physics course, interactive quizzes pulling from a database of hundreds of old Regents Physics Exam questions, video tutorials of every major topic covered by the exam, and is also tied in quite closely with the Regents Physics Essentials review book. In addition, every Regents Physics questions from the past 16 exams has been pulled into worksheets by topic to allow for highly directed practice. ScienceWithMrNoon: Brendan Noon‘s physics site has a wide variety of great content, including topic-based interactive quizzes and tons of great physics videos. His course calendar, as well, is loaded with tons of great resources by topic! St. Mary’s Physics: Tony Mangiacapre‘s site, full of great lessons and interactive simulations across the entire Regents Physics curriculum. I’m especially fond of the Photoelectric Effect simulation — makes for a great computer-based lab activity! This site is also closely linked with Tony’s 123physics.com, featuring more than 1300 Regents Physics Exam questions broken down by topic for students to practice, as well as more great videos. RegentsPrep.org: The Oswego City School District (with Dr. Tom Altman) has pulled together a strong collection of resources broken into Explanations, Demos, Labs, and Quizzes to assist students and educators in preparing for the Regents Physics exam. Altman Science: The charismatic Dr. Tom Altman provides real-life demonstrations and explanations of physics concepts in action as part of the High School Physics Project. Further, he’s broken down a number of old Regents Exams and walked through solutions to each and every question in video format, page by page. In addition, his laser videos are “wicked cool” as well! Past Regents Exams: The name says it all — an amazing archive of old Regents Physics exams! Regents Physics Essentials: I’d feel negligent in my feeble attempts at self-marketing if I didn’t point out the Regents Physics Essentials review book I put together at student urging a few years back. There are a number of great review books to help students get ready for the exam, but this book takes a slightly different twist by providing students a straightforward, clear explanation of the fundamental concepts and more than 500 sample questions with fully-worked out solutions directly integrated in the text. As stated by my physics teaching cohort in crime at our high school, “the best review book is the one students will actually use,” and this was written to be friendly, fun, and concise. Plus, if students/teachers want extra problems without solutions given, the worksheets are available free online! You can check out the book’s free preview on APlusPhysics or use Amazon’s “Look Inside” feature! Source

I haven't seen it yet, but it's been on my list of shows "I someday want to watch when I get caught up." I've heard good things about it!

Walter Lewin provides a great explanation of rainbows at roughly 16 minutes into the video.

Hello high school physics teachers! My name is Rob Pearson, and I’m director of microelectronic engineering programs at Rochester Institute of Technology. I really like what I do and I want to tell you why. I also want to tell you why I am sharing this with you. I bet you would like to see students more engaged with the concepts you teach and the math employed in your courses. I am an engineer, so I think about problem solving (applications) first and basic science second. But like any good engineer (think MacGyver, to use an outdated reference) I know that I need to be handy with tools like math and physics if I am going to do anything useful. Come to think about it, why didn’t MacGyver ever say he was an engineer? What if your student could help solve challenging problems, use math and science every day, and have a rewarding career and also make a good salary? Typical bachelor of science graduates of RIT’s microelectronic engineering program receive multiple job offers with average starting salaries in the $60-70k range. Now back to what I do as an electrical engineer. Some aspects of electrical engineering can be dry and theoretical, but I fabricate semiconductor devices — millions of them on a chip and billions of them on each silicon wafer. The process of making these “magical” semiconductor systems is intricate and uses lots of physics, optics, mechanics, chemistry, you name it. So how does this relate to your physics course? Let me give you some examples. You teach about the Lorentz force and the right-hand rule. You could use a motor winding to illustrate the usefulness but I can give you another example the mixes physics and chemistry. We introduce elements from groups III and V on the periodic table into silicon (group IV) to change the conductivity of the silicon and make our devices. One way to introduce these elements is by ion implantation. Ion implanter functionality is based on the Lorentz force. We use tunable electro-magnets to sort ions in a vacuum by mass to charge ratio and then accelerate them using a variable high-voltage (200,000 V) supply. There is plenty of physics to talk about in this tool. Another example is a micro-electro-mechanical system (MEMS) device called an accelerometer. It consists of a tiny mass on a tiny beam and when the mass is accelerated it produces a proportional electrical signal. But wait, there’s more! It’s great that I can use these basic science courses and concepts in what I do, but what I really like is communicating the exciting possibilities of what has yet to be designed and built. Look at the changes that have occurred in our phones over just the last five years! They have touch screens, accelerometers, Global Positioning Systems, maps, computers, music players, TVs, videos (3D too!)… they can be video projectors, photo albums, and gaming systems. And that’s just one of many systems that rely on semiconductor products. What will your students do if they take up a career in this challenging field? Do you remember the tricorder that Dr. McCoy had on Star Trek? That portable medical lab in one compact unit is nearing reality. Great strides are being made in the intersection of electronics, biology, and chemistry. Further miniaturization of electronics is needed to take our current sci fi tech and turn it into practical high tech. The biggest challenge I face running an undergraduate college engineering program that focuses on microelectronics and semiconductor processing is finding bright young high school students who even know that this field exists. Please help us spread the word. I hope that maybe you can encourage an interested student or two of yours to go on to study microelectronics or nanotechnology in college, and invite you to learn more about our programs and microelectronics by visiting our web page at http://www.rit.edu/kgcoe/ue/. Sincerely, Rob Pearson, PhD Director, Microelectronic Engineering Programs Rochester Institute of Technology robert.pearson@rit.edu (Please note that further information about semiconductors and microelectronics in high school can be found as part of the Semiconductor Technology Enrichment Program materials available at APlusPhysics.com. Special thanks to Dr. Rob Pearson for submitting his article as a guest post to Physics In Flux.) Source

Hello high school physics teachers! My name is Rob Pearson, and I’m director of microelectronic engineering programs at Rochester Institute of Technology. I really like what I do and I want to tell you why. I also want to tell you why I am sharing this with you. I bet you would like to see students more engaged with the concepts you teach and the math employed in your courses. I am an engineer, so I think about problem solving (applications) first and basic science second. But like any good engineer (think MacGyver, to use an outdated reference) I know that I need to be handy with tools like math and physics if I am going to do anything useful. Come to think about it, why didn’t MacGyver ever say he was an engineer? What if your student could help solve challenging problems, use math and science every day, and have a rewarding career and also make a good salary? Typical bachelor of science graduates of RIT’s microelectronic engineering program receive multiple job offers with average starting salaries in the $60-70k range. Now back to what I do as an electrical engineer. Some aspects of electrical engineering can be dry and theoretical, but I fabricate semiconductor devices — millions of them on a chip and billions of them on each silicon wafer. The process of making these “magical” semiconductor systems is intricate and uses lots of physics, optics, mechanics, chemistry, you name it. So how does this relate to your physics course? Let me give you some examples. You teach about the Lorentz force and the right-hand rule. You could use a motor winding to illustrate the usefulness but I can give you another example the mixes physics and chemistry. We introduce elements from groups III and V on the periodic table into silicon (group IV) to change the conductivity of the silicon and make our devices. One way to introduce these elements is by ion implantation. Ion implanter functionality is based on the Lorentz force. We use tunable electro-magnets to sort ions in a vacuum by mass to charge ratio and then accelerate them using a variable high-voltage (200,000 V) supply. There is plenty of physics to talk about in this tool. Another example is a micro-electro-mechanical system (MEMS) device called an accelerometer. It consists of a tiny mass on a tiny beam and when the mass is accelerated it produces a proportional electrical signal. But wait, there’s more! It’s great that I can use these basic science courses and concepts in what I do, but what I really like is communicating the exciting possibilities of what has yet to be designed and built. Look at the changes that have occurred in our phones over just the last five years! They have touch screens, accelerometers, Global Positioning Systems, maps, computers, music players, TVs, videos (3D too!)… they can be video projectors, photo albums, and gaming systems. And that’s just one of many systems that rely on semiconductor products. What will your students do if they take up a career in this challenging field? Do you remember the tricorder that Dr. McCoy had on Star Trek? That portable medical lab in one compact unit is nearing reality. Great strides are being made in the intersection of electronics, biology, and chemistry. Further miniaturization of electronics is needed to take our current sci fi tech and turn it into practical high tech. The biggest challenge I face running an undergraduate college engineering program that focuses on microelectronics and semiconductor processing is finding bright young high school students who even know that this field exists. Please help us spread the word. I hope that maybe you can encourage an interested student or two of yours to go on to study microelectronics or nanotechnology in college, and invite you to learn more about our programs and microelectronics by visiting our web page at http://www.rit.edu/kgcoe/ue/. Sincerely, Rob Pearson, PhD Director, Microelectronic Engineering Programs Rochester Institute of Technology robert.pearson@rit.edu (Please note that further information about semiconductors and microelectronics in high school can be found as part of the Semiconductor Technology Enrichment Program materials available at APlusPhysics.com. Special thanks to Dr. Rob Pearson for submitting his article as a guest post to Physics In Flux.) Source

I would find the area of each side (the thin tube and the barrel) using Pi*r^2. Then, you know that the pressures must be equal, so the F1/A1 = F2/A2. Solve for F1 by finding the mass of the water in the tube (volume * density), then its weight (mg), and that's the F1. From there, you should be able to calculate F2. For further details, I'd refer you to Honors Physics Essentials, p. 181-183. Good luck!

Per request, a short (6 minute) video that gives an overview of the particle accelerator at CERN.

Theoretically you are correct, you would have an infinite current and things would blow up. Practically, however, voltage sources have some internal resistance, as do wires, and in many cases, the capacitors themselves. But in general, you typically want a resistor somewhere in your circuit any time you have a capacitor involved to limit the current (errrr, damage) you may cause.

I'll pass that along and see what sorts of interest it generates. Like the blackboard!!! How's college life treating you?

I think you have a slight algebra error based on the directions of the forces. We can take a look in class, but there should be two points on the axis where the net force is 0.

[ATTACH=CONFIG]316[/ATTACH]The Rochester Area Physics Teacher's Out Reach (RAPTOR) will hold its first meeting of 2012 at the Rochester Institute of Technology on Saturday, January 14th from 9 am-noon EST.* Physics education enthusiasts all over the world are welcome to attend this meeting live via this link. The meeting will feature a presentation by Dan Fullerton, author of Regents Physics Essentials, Honors Physics Essentials, and developer of APlusPhysics.com, as well as a presentation and discussion centered around physics lessons addressing New York's Common Core State Standards and how these changes will affect physics education. Come for the free donuts and stay for the demos, and if you can’t attend in person, join us online! Special thanks to Brendan Noon of Science With Mr. Noon for organizing this event.