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  3. Supersonic speed

    If you have a chance, read up a bit on Chuck Yeager (and/or follow his Twitter). An amazing man with an amazing career and a fantastic sense of humor to boot.
  4. What Is This and Why Is It Important?

    Love this! My background is in microelectronic engineering, and I'm even in the middle of putting together a 2-hour workshop on microelectronics (presentation is in December) that will cover much of what you did over the summer. Great discipline, with TONS of fantastic jobs that are fun, challenging, and rewarding. We'll have to talk more...
  5. What Is This and Why Is It Important?

    What is this? Over the summer I participated in Photon Camp at the University of Rochester with a few classmates. It was an awesome experience by the way! The main reason I’m here is to talk about the project I worked on in a group of 4. Each student had a different project. So, if you need an idea for a blog post, there you go. My group was studying photolithography which is the process of creating patterns using light. We worked with Professor Bryan McIntire and were able to go into the clean room and actually perform the process on a series of silicon wafers coated in the photoresist. The first step was to coat the plate in primer, which applied via spin adhesion, so that a layer 1.4 micrometers thick was evenly spread across the surface. Then it was time to perform the actual process. The main component which allows this process to work is the photoresist. There are two kinds: positive, which breaks down when exposed to light, and negative, which polymerizes when exposed to light. We used a negative photoresist when exposing our wafers to light. We performed two different processes when exposing them. In the first, UV light can be run through a mask, projecting the image of the mask onto the surface coated in the photoresist. The other option was to laser-write, by placing the wafer under a 405 nanometer laser, exposing the wafer in a designated pattern. The chemical structure of the photoresist is changed, becoming soluble and then is washed away, revealing the Silicon Dioxide layer underneath. The etching process is next, using Hydrofluoric acid to wash away the Silicon Dioxide. Afterwards, the wafer is washed with Acetone, removing the protective layer, and showing the true colors of the wafer. If the piece is multiple layers, then Hydrofluoric Acid would be withheld and another layer of Silicon Dioxide can be placed over the first layer to act as a base layer for photoresist to be applied onto. In the final step, the Silicon Dioxide between layers is removed, leaving only silicon, creating the final product. So why is this important? Large amounts of energy and money go into cooling the information systems we use on a daily basis. As internet usage increases so will the amount of facilities and power needed to support this. It is theorized this system will not be viable in the future without breakthroughs in energy production, but photonics may promise another solution. Using photonics to transmit information does not create nearly as much heat, causing many scientists to look to it as a way to alleviate the dependence on energy used to cool electronics. The process of making technology more compact is hindered greatly by the amount of transistors which would be located on an integrated circuit. A concept referred to as Moore's Law states that the amount of transistors on a given area for the same price doubles every two years. The process of photolithography is the next step in this process as the resolution achieved using smaller wavelengths allows for a dramatic increase in the concentration in the amount of transistors placed. The resolution achieved by EUV radiation can be 18nm. Looking further past this, in order to get an even better resolution, a process using an electron beam would be needed. Photonics may hold the solution to the problem it has created. Equation for resolution (how small the patterns can be) R~ (Wavelength)/(Numerical Aperture) Here are some pictures of the wafers we made: This is the first plate which we made light channels on. This image shows two waveguides(light tunnels) converging. Each waveguide measures 2 microns across. Some professors use this to study how light rays behave as they get close to one another. This is the second plate that had a series of patterns etched onto it in order to create different types of diffraction gratings. These dots were made by drawing lines 5 microns wide and are the same ones shown in the first image of this blog. This picture shows the edge of a horizontal diffraction grating. And finally this is the third plate which the universities crest was etched on. Thanks for reading, and if you have any younger siblings interested in the camp I highly recommend it! -ThePeculiarParticle
  6. How Do Pickups Work?

    Yes, there has been some delay between posts, I apologize, but life is busy as usual. This week I wanted to cover the topic of pickups for string instruments. So I play electric bass and wondered the other day how different pickups get different tones and sounds out of them. You can have warm, mellow, fuzzy, even screechy tones all based on the different models. To answer this, we need to see how a pickup actually “picks up” the string vibrations, and it does so through Faraday’s Law. Faraday’s Law states that changing a magnetic field creates an electric current. Now the magnets mounted on the instrument are static, but the strings which vibrate are not. The vibration of a string disrupts the field and causes an electrical signal to be the output. The only time this is a problem is when a harmonic results in a node occurring over the pickup and register as silent due to the string not oscillating at that point. This is where multiple pickups can be handy as they can add a signal together if both register a frequency or one can register a frequency if the other has a node above it. Here is a picture of the system used to pick up an electrical signal. Many pickups are single coil as shown by a single row of magnets. While this may be a cheaper option, it is more prone to interference from surrounding equipment and signals. The most commonly used alternative is a Humbucker. Humbuckers work by using two coils housing magnets of opposite polarity. This creates signals out of phase in each coil. If these coils connect correctly it results in external electromagnetic fields, such as from power lines, to be canceled out and the guitar signal is doubled. This diagram shows a simple circuit for a pickup. The resistor for tone effectively acts as a filter for higher level frequencies. Adjust the resistor and the frequencies which get cut also changes. The resistor bellow controls volume or amplitude of the signal before it travels through the cable to the larger amplifier. Every single one differs slightly so that the signals to every pickup on an instrument can combine and create a unique sound. Thanks for reading! -ThePeculiarParticle
  7. Last week
  8. Analyzing the forces acting on a bucket of water which is revolving in a vertical circle. Want Lecture Notes? This is an AP Physics 1 topic. A big thank you to Mr. Becke for being a guest in today’s video! Content Times: 0:11 The demonstration 0:24 Drawing four Free Body Diagrams 1:30 Summing the forces with the bucket at the bottom 2:27 What is the centripetal force? 3:28 Why the Force Normal greater than the Force of Gravity with Mr. Becke! Multilingual? Please help translate Flipping Physics videos! Previous Video: Demonstrating Why Water Stays in a Bucket Revolving in a Vertical Circle Please support me on Patreon! Thank you to Aarti Sangwan and Christopher Becke for being my Quality Control Team for this video.
  9. Name: Analyzing Water in a Bucket Revolving in a Vertical Circle Category: Rotational Motion Date Added: 2017-10-15 Submitter: Flipping Physics Analyzing the forces acting on a bucket of water which is revolving in a vertical circle. Want Lecture Notes? This is an AP Physics 1 topic. A big thank you to Mr. Becke for being a guest in today’s video! Content Times: 0:11 The demonstration 0:24 Drawing four Free Body Diagrams 1:30 Summing the forces with the bucket at the bottom 2:27 What is the centripetal force? 3:28 Why the Force Normal greater than the Force of Gravity with Mr. Becke! Multilingual? Please help translate Flipping Physics videos! Previous Video: Demonstrating Why Water Stays in a Bucket Revolving in a Vertical Circle Please support me on Patreon! Thank you to Aarti Sangwan and Christopher Becke for being my Quality Control Team for this video. Analyzing Water in a Bucket Revolving in a Vertical Circle
  10. Supersonic speed

    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.
  11. Force of a Linebacker

    Old Silverback is my favorite player!
  12. Appendix A physics 1 kinematics

    Which is certainly closely enough given various rounding / sig figs. You got it right.
  13. Earlier
  14. Force of a Linebacker

    This weekend I watched a lot of football. Watching it this week made me realize how bad it must hurt to get hit by a 240+ pound linebacker. The average running back runs about 4.72 m/sec and has a mass of about 97.5 kg. If the linebacker stops the running back in 1 second, the force on the running back is about 460 newtons. Due to newtons third law, that same force is thrown onto the linebacker as well. A linebacker that is famous for his powerful tackles is James Harrison for the Pittsburgh Steelers. He is 125 kg... Sometimes football is better to be watched then played.
  15. Newton's Second Law Lab

    Last week in physics, we completed what was called the Newton's second Law Lab in groups, in which we were to determine the mass of a cart without using any scales or balances. The procedure was only meant to take us one, maybe two, class periods. However, our group went into a third period. We kept trying to collect new data because we had a larger percent error than we would have liked and assumed we were doing something wrong. We ended up spending a lot more time trying to get better results than we should have, and then learned that our results were fine to begin with and that we had done nothing wrong except waste time trying to get better ones. Because of this, we have now lost some class time to get other things done. We now know that sometimes results may not look exactly the way you want them to in a lab, even when you're doing everything right. In the future, we won't let results that aren't perfect hold us back when we know what we did was correct.
  16. Appendix A physics 1 kinematics

    Using the kinematic equations I had 1 = 0*1.52 + .5*a*1.522. Solving for a I got 0.865 m/s/s but the book says the answer is .855 m/s/s.
  17. Appendix A physics 1 kinematics

    There are several explanations I think. I would probably use the kinematic equations (v0, v, delta_x, a, t), and use those to solve the problem. If you're getting stuck, can you post what you've done so far, and that will give me better information to assist you?
  18. Appendix A physics 1 kinematics

    I need help solving question 7 in the APlus Physics 1 essentials book in appendix A on kinematics. There isn't much of an explanation for the answer. Thanks!
  19. Name: Demonstrating Why Water Stays in a Bucket Revolving in a Vertical Circle Category: Rotational Motion Date Added: 2017-10-08 Submitter: Flipping Physics Yes, water stays in the bucket. Would you like to know why? Watch the video and learn! Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:14 The demonstration 0:52 Why does water flow out of a bucket? 1:40 Inertia! 2:38 Visualizing why Multilingual? Please help translate Flipping Physics videos! Previous Video: Determining the Force Normal on a Toy Car moving up a Curved Hill Please support me on Patreon! Thank you to Aarti Sangwan and Christopher Becke for being my Quality Control Team for this video. Demonstrating Why Water Stays in a Bucket Revolving in a Vertical Circle
  20. Yes, water stays in the bucket. Would you like to know why? Watch the video and learn! Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:14 The demonstration 0:52 Why does water flow out of a bucket? 1:40 Inertia! 2:38 Visualizing why Next Video: Analyzing Water in a Bucket Revolving in a Vertical Circle Multilingual? Please help translate Flipping Physics videos! Previous Video: Determining the Force Normal on a Toy Car moving up a Curved Hill Please support me on Patreon! Thank you to Aarti Sangwan and Christopher Becke for being my Quality Control Team for this video.
  21. 2D Motion Homework Help

    Hi cjt100. So we can better assist, can you tell us what you've tried so far, and where you're getting stuck?
  22. 2D Motion Homework Help

    At t = 0, a particle leaves the origin with a velocity of 18.7 m/s in the positive x direction and moves in the xy plane with a constant acceleration of (-1 i + 4 j) m/s2. At the instant the y coordinate of the particle is 18 m, what is the x coordinate of the particle?
  23. Ping Pong Physics

    Cool video edits!!!
  24. LaTex Help.

    Sure would be nice if your teacher put something together to help with LaTeX and getting started... maybe something like a guide and even starting templates. Perhaps even a video guide? http://www.aplusphysics.com/about/LaTeX.html
  25. Dynamics supplement question 19

    Thanks for the insights! I appreciate the help.
  26. Dynamics supplement question 19

    This is a very common type of question, and the process of breaking up forces on a FBD into components and applying Newton's 2nd Law carries throughout the entire course. One of those things you've gotta learn. The "shortcut" that you learned isn't really a shortcut, and isn't something I'd recommend, as it won't carry through to other situations in which the third force isn't caused by gravity on a mass. I'd focus on learning how to draw free body diagrams, break forces at angles into components, and applying Newton's 2nd Law. It's the backbone of mechanics, and very important in further units as well. Good luck!
  27. The Physics Behind an MRI

    This was a really awesome read! It reminds me of a video I saw a few weeks back, and while it isn't as informative, the experiments are really cool. The power these magnets have is simply incredible...
  28. Gravitational Waves 2017 (Not Clickbait)

    Besides acting as an eye catching graphic, this animation shows the interaction between two bodies which causes gravitational waves. Amidst increasing international and domestic tensions, it is hard to find any news agencies talking about 1.8 billion year old news anymore. This week, LIGO observatories announced the detection of gravitational waves back in August caused by two colliding black holes. It is estimated that both black holes had the mass of 53 suns. As for what gravitational waves are, they are ripples in spacetime caused by usually very large gravitational interactions. This is not the first time they have been detected. The two VIRGO observatories, one located in Washington and one located in Louisiana, were able to narrow down the region of space for prior waves origins to arcs which could fit over 3000 full moons. A new detector in Italy, named Virgo, became the key piece in triangulating this signal to a smaller point in space of only 300 full moons. This image shows the areas of detection for the previous gravitational phenomena projected onto a spherical representation of the milky way. The latest (GW170814) is substantially smaller in area than the others. As for why this matters, within the next few years another LIGO detector is scheduled to go online in India and another, named KAGRA, in Japan in order to make this area smaller. The more observatories we have means more accurate readings and decreases the likelihood of any false signals. The more data we can receive the more we can learn about the behavior of the universe. This latest reading confirms that gravitational waves have 3 dimensional polarization further proving another part of relativity. In the future, scientists wish to learn more about the exact moment of the collision, specifically, if they are lucky enough to catch two neutron stars and see any radiation. They also wish to know if any matter or light is emitted from these collisions. Frankly, the information we know about is practically nothing. At this point, any data is vital to expanding our understanding of the universe and bring some method to its madness. Hope everyone enjoys their week and puts their ear to the ground on any future information. -ThePeculiarParticle I don't claim to be an expert in this field. In fact, I am not even close, so if you wish to know more here is the link to their website: https://www.ligo.caltech.edu/news
  29. Name: Determining the Force Normal on a Toy Car moving up a Curved Hill Category: Rotational Motion Date Added: 2017-10-02 Submitter: Flipping Physics A 0.453 kg toy car moving at 1.15 m/s is going up a semi-circular hill with a radius of 0.89 m. When the hill makes an angle of 32° with the horizontal, what is the magnitude of the force normal on the car? Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:08: Translating the problem 1:01 Clarifying the angle 1:51 Drawing the free body diagram 3:20 Summing the forces 4:22 How the tangential velocity and force normal change Multilingual? Please help translate Flipping Physics videos! Previous Video: Mints on a Rotating Turntable - Determining the Static Coefficient of Friction Please support me on Patreon! Thank you to Aarti Sangwan, Scott Carter, and Christopher Becke for being my Quality Control Team for this video. Determining the Force Normal on a Toy Car moving up a Curved Hill
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