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  1. Yesterday
  2. Bees?

    Is this a bee movie reference?
  3. The Weight of Air (and birds)

    Hold up, if lil peep is no longer with us and the peeps candy are modeled after ducks, is this post pretty much a eulogy. I selected option C in the very beginning so I should have some say in the prize given. A carton of peeps candy would do nicely.
  4. Quantum Leap

    This is the truth.
  5. Quantum Leap

    your chemistry class sounds cool
  6. The Weight of Air (and birds)

    Commonly pondered question: How much does all the air on the Earth weigh? Make your predictions now: a) more than the Earth itself 0 kg, air weighs nothing, duh c) More than all the birds on Earth d) 7.89 kg One cubic meter (1000 liters) of air weighs 1.292 kg (so if you chose d you are probably already wrong) But that doesn't help us much, because as you go further up in the atmosphere, the density changes. The mass of the air is the same, but there is just less of it per cubic meter. Calculations: Another way to approach this problem: the air pressure at sea level is 14.7 psi, in other words, all the air in a 1in x 1in area all the way up to the top of the atmosphere would weigh 14.7 lbs ***we'll convert to more physics like units later*** Now we need to find out the surface area of the Earth: Earth's radius: 2.5E8 in (again we'll convert later) Surface area of a sphere: A = 4*pi*r2 = 7.854E17 in2 Now multiply: 7.854E17 in2 x 14.7 lbs/in2 = 1.155E19 lbs All the air in the Earth's atmosphere weighs approximately: 5.3E14 kg Compared to: All the birds on the Earth: net weight(very approximately) = 3.6E12 kg (if you chose c at the beginning, you win *suggest prizes in the comments*) The Empire State Building(approximately) = 3.3E8 kg 500 really big boulders(exactly) = 3.4E4 kg
  7. Last week
  8. Quantum Leap

    The colloquialism "quantum leap" has uses beyond conversation. It describes atomic orbital transitions as electrons "leap" from energy level to another and in the process they either absorb or energy in the form of photons. "Quantum leap" is also used as a figure of speech, a short hand metaphor in language. The idiom may connote a change in something's character, a greater change in energy or excitement or even a "leap of faith" or "jump to conclusions". In my chemistry class, the notes had contained this phase when describing the phenomenon and because the notes somethings took on a conversational tone, I could not confidently differentiate between the two cases. Perhaps this is proof that science is becoming more mainstream, maybe I'm lunatic but believe that understanding many things enriches our involvement with study, that nothing is truly separate. In this way it may be important to know this trivial details.
  9. Name: How Much is a Mermaid Attracted to a Doughnut? Category: Circular Motion & Gravity Date Added: 2017-11-20 Submitter: Flipping Physics How Much is a Mermaid Attracted to a Doughnut? A practical, everyday example of Newton’s Universal Law of Gravitation. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:08 Translating the problem 0:42 The Force of Gravity Equation 1:47 Solving the problem 2:24 How to do “times ten to the” on your calculator 2:45 Correcting our mistake 3:42 Visualizing these forces 4:14 Why do the objects not move? 5:36 What if the mermaid and donut were the only two objects in the universe? Multilingual? Please help translate Flipping Physics videos! Previous Video: Newton's Universal Law of Gravitation Introduction (The Big G Equation) Please support me on Patreon! Thank you to Eric York, Scott Carter, Jonathan Everett, and Christopher Becke for being my Quality Control Team for this video. Thank you to Youssef Nasr for transcribing the English subtitles of this video. How Much is a Mermaid Attracted to a Doughnut?
  10. How Much is a Mermaid Attracted to a Doughnut? A practical, everyday example of Newton’s Universal Law of Gravitation. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:08 Translating the problem 0:42 The Force of Gravity Equation 1:47 Solving the problem 2:24 How to do “times ten to the” on your calculator 2:45 Correcting our mistake 3:42 Visualizing these forces 4:14 Why do the objects not move? 5:36 What if the mermaid and donut were the only two objects in the universe? Multilingual? Please help translate Flipping Physics videos! Previous Video: Newton's Universal Law of Gravitation Introduction (The Big G Equation) Please support me on Patreon! Thank you to Eric York, Scott Carter, Jonathan Everett, and Christopher Becke for being my Quality Control Team for this video. Thank you to Youssef Nasr for transcribing the English subtitles of this video.
  11. The Wizard of Oz

    Over the weekend, the movie the Wizard of Oz was playing on TV and my mother was reminiscing about how she was so mesmerized by the colorful movie when she first saw it. This inspired me to do some more research on what is commonly (but mistakenly) thought of as the first movie made in color and how it was filmed. The Wizard of Oz was filmed in Technicolor, which was also the name of a corporation developed by two physics professors from MIT. An article from the MIT Technology Review titled The Advent of Technicolor says that in the initial model of the Technicolor camera, it "split the light from a scene to simultaneously expose two adjacent frames on the negative, one behind a red filter and the other behind a green filter. As the film ran through a projector, separate beams of light passed through the identical frames; focused by a prism, they combined into a single color image on the screen." This method ended up being pretty difficult to perfect and inefficient, however it touches on the spectrum of light and the effect on light after passing through a prism. I enjoyed learning about this in physics last year and I hope to learn more about this process in the future. I also included a video that touches on how a modern digital camera works as well as how the human eye works. I can't believe how much I learned and I can't wait to learn more!
  12. But how did Sylvestor get across the ravine?
  13. Why We Lower the Third

    Fantastic application of physics to music. Cool!!!
  14. AP Physics 1 Essentials question: Dynamics

    Draw separate free body diagrams for each of the objects, showing the direction of the forces on each object. For example, for the (2m) mass, you would have a dot with an arrow to the left (T3), and an arrow to the right (T2). The up and down arrows (forces Fn up and mg down) are balanced, so we'll focus on the x-direction. Writing Newton's 2nd Law in the x-direction, since T2 is in the positive direction, we'll leave it as positive, and since T3 is in the -x direction, it will be negative. Therefore T2-T3 = (2m)a.
  15. Earlier
  16. Page 80, question #4.12 in the book... I'm not understanding the worked out solutions, especially why the tensions were subtracted. Explanations would be appreciated
  17. Bees?

    There's a common myth that bumble bees shouldn't be able to fly because of the size of their bodies. It's not entirely certain where this myth comes from, but mostly it's because, for whatever reason, someone making these calculations didn't take into account all factors. The wings of a bumble bee bend and move back and forth in addition to up and down. This is meant to create vortices above the wing such that the "eye" of the vortices have low pressure compared to the surrounding air, which allows the bee to fly. This concept is similar to how a plane flies in that the low pressure above the wings creates a force called lift; when air moves faster, the pressure of the air decreases. The actual way bees and planes produce those low pressure areas are different, of course; planes don't create vortices but are shaped so that the air above the wing travels faster than the air under it. So in conclusion, there's a physics explanation for everything--including the flight of a bumble bee.
  18. Name: Newton's Universal Law of Gravitation Introduction (The Big G Equation) Category: Circular Motion & Gravity Date Added: 2017-11-12 Submitter: Flipping Physics Understanding Newton’s Universal Law of Gravitation. Including a dramatization of The Cavendish Experiment and force visualization via qualitative examples. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:11 Reviewing the standard Force of Gravity or Weight equation 0:56 Newton’s Universal Law of Gravitation 1:48 Defining r 2:47 The Cavendish Experiment 3:52 Visualizing qualitative examples 5:59 When to use the two Force of Gravity equations Thank you to Bronson Hoover of dnbstudios for letting me use his original composition Bèke as Henry Cavendish’s background music. Multilingual? Please help translate Flipping Physics videos! Previous Video: Conical Pendulum Demonstration and Problem Please support me on Patreon! Thank you to Scott Carter, Jonathan Everett, and Christopher Becke for being my Quality Control Team for this video. Newton's Universal Law of Gravitation Introduction (The Big G Equation)
  19. Understanding Newton’s Universal Law of Gravitation. Including a dramatization of The Cavendish Experiment and force visualization via qualitative examples. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:11 Reviewing the standard Force of Gravity or Weight equation 0:56 Newton’s Universal Law of Gravitation 1:48 Defining r 2:47 The Cavendish Experiment 3:52 Visualizing qualitative examples 5:59 When to use the two Force of Gravity equations Next Video: How Much is a Mermaid Attracted to a Doughnut? Thank you to Bronson Hoover of dnbstudios for letting me use his original composition Bèke as Henry Cavendish’s background music. Multilingual? Please help translate Flipping Physics videos! Previous Video: Conical Pendulum Demonstration and Problem Please support me on Patreon! Thank you to Scott Carter, Jonathan Everett, and Christopher Becke for being my Quality Control Team for this video.
  20. Physics of Slinkies

    I think almost everyone has seen a slinky “slink” down a flight of stairs. At the top of the stairs, the slinky has stored potential energy and won’t move until someone acts on it. It’s not until someone begins the slinky’s movement does it begin to move, converting that potential energy into kinetic. Each time the slinky falls from one step to another, more gravitational potential energy is changed to kinetic. But not only that, energy is transferred along the slinky in the firm of compressional waves which travel along the metal coils, causing it to stretch and compress. Of course, since it's in motion, the slinky also develops momentum. The horizontal component of the momentum is what keeps it traveling down the stairs; if the stairs were wider and the slinky couldn't reach the end, it would stop moving, but when it is carried over the edge of the stairs, more and more gravitational potential energy is converted to kinetic and the slinky keeps going until it reaches the bottom.
  21. Why We Lower the Third

    I've been finding that most (all?) of the things Mr. Springstead tells us in band have a reason grounded in physics. For example: when playing a major chord consisting of the root, third, and fifth, he often tells us the third note should be slightly lower. Notes that sound "good" together, such as the notes of a basic major chord, sound that way because their wavelengths "meet up" at regular intervals. Mathematically, we can look at the ratio of each note's frequency. The ratio of C4 (middle C) to G, the fifth note of a C major scale, is (approximately) 3/2, so every third G wave meets up with every second C wave. The ratio of C to E is approximately 5/4. But in reality, that ratio is slightly off. 329.63 Hz, the frequency of E4, divided by 261.63, the frequency of middle C, is actually 1.25991. (Likewise, the frequency of G4 divided by middle C is 1.498.) Clearly, none of these ratios are perfect, but the third of the notes is slightly more off than the fifth with a percentage difference of 0.79% vs. 0.133%. And so, to correct this (barely perceptible) problem, we try to play the third note slightly lower than normal.
  22. One of the cool things about The Martian is "seeing" physics in action somewhere other than our planet. In most physics examples, we have things like friction or air resistance to contend with; after all, friction is everywhere. When we were first learning that an object with velocity but absolutely no net force acting on it would just keep moving without slowing down, it didn't seem to make sense at first (at least it didn't to me)--because every object we'd seen moving had been experiencing friction or air resistance. But space is a pretty good vacuum; there's almost nothing out there to brush against and create friction. In the novel, Hermes experiences constant acceleration on its journey from Mars back to Earth, and, as a result, its final velocity was huge. Nothing was really slowing it down, so it just gathered more and more speed until the month before it was the reach Earth, as at that point it was traveling so quickly it need that entire month to decelerate enough to slow down to Earth's speed. Cutting the acceleration wouldn't stop the craft's velocity; it would continue traveling at its speed until it began to accelerate in the opposite direction. Of course (spoilers) Hermes doesn't decelerate, instead deciding to do the "Rich Purnell Maneuver" and continue to accelerate past and around Earth, using the pull of gravity to adjust their course and head back to Mars. Its constant-thrust ion engine, which allowed Hermes to constantly accelerate, made it the spacecraft thing fast enough to get to Mars in time to bring food to Mark before he starved.
  23. Violin Blog 3: Tuning

    It's so cool learning about things in music and then learning why these things happen in physics. If you think about it, most of music is physics.
  24. What is Onix Made Of?

    That's a whole lotta math! Well, you know what they say... gotta catch em all. Or in this case, Gotta catch all of em, meaning all of this ginormous baby powder beast into a tiny pokeball.
  25. Interesting Conversations

    I remember this conversation! It was strange to think that, since the earth pulls on us, we pull on the earth back because of Newton's third law. Physics is weird.
  26. A Sonic Boom of Light

    Oh no.. I posted about the same thing and only now just realized. Oops again!
  27. Hubble Space Telescope

    It would be so cool to work here one day.
  28. Why I spent $250 on a Swim Suit for Sectionals 2017

    Hm... Still sounds like a waste of money to me! Just joking
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