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DanDuguay

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Blog Entries posted by DanDuguay

  1. DanDuguay
    Many of us enjoy looking at optical illusions, but why do our eyes lie to us?????

    Although each illusion has it's own reason, and scientists still don't know all the reasons, it comes down to one thing. Our brain makes assumptions.

    Our brain uses context of our surroundings to make split second assumptions. This is helpful in everyday life and back when we were hunters and gatherers and needed to make split second decisions in the wild. Our eyes don't show us what's really there just what we need to see. It uses the surrounding environment to make conclusions. This is done by using shadows, surrounding colors, and past experiences.



    optical illusions are just a case of your brain telling you what you should be seeing, not what is actually there.
  2. DanDuguay
    The physics behind a hockey check is fairly simple. It is a basic collision. One force, the checker, is coming in with a mass and acceleration, onto and another player with a separate mass and acceleration. As Newton's law states, every action has an equal and opposite reaction. So the player with a bigger mass will be able to absorb more of the hit, and a smaller player, much less so.

    The Player who was hit will stay in motion unless acted upon by an outside force. A lot of times this is the boards. Many injuries occur by players going into the boards with a lot of force. The boards are unforgiving and do not have a lot of give meaning a short impact time witch means a lot more pain for the person being checked.

    However if a player is against the boards, he will be much safer when checked. The collision force would be transferred from the player to the boards back to the player and back to the original checker. For example, if a player gets hit by a 20N force, he will then transfer 20N to the boards but some of that force would come right back because of a recoil. This is why you often see the original checker fall down after making a check on someone who is along the boards.

    Lastly the players momentum is the ultimate determinate of the strength of the check. Momentum (p=mv) is constantly changing while on the ice. The players mass is a constant, so in order to increase their momentum, players will go faster. Higher velocity means more momentum, means bigger collision.
    Checking is an important part of the game and is all just applying forces to other players. So in conclusion, in order to deal the biggest hit, you want to maximize your mass and velocity, and when taking a hit, try to have the boards absorb the hit rather than just you.
  3. DanDuguay
    The selfie is something that has become hugely popular. People are constantly taking pictures with their phones and this has become a common part of our culture. With all these people taking pictures on their phones, the question arises, is it worth it to buy a camera or just use your phone?

    The major camera type is a DSLR ( digital single lens reflex). The DSLR I use for comparison is a Nikon D80 which is a pretty average DSLR so it will be a good representation of the average. There are many differences between the two. the first difference is in the lens structure. The iPhone has a five element fixed lens system. This means that there are a total of 5 lenses in the iPhone camera and they cannot move independently. This limits the phones ability to focus at different ranges. The average DSLR has a 16 element detachable lens system meaning that it has 16 lenses that can all move independently from each other. This allows for a much greater focus at every distance.

    The cameras also have different sensors in them. The iPhone has an 8 megapixel CMOS sensor. A CMOS sensor is cheap to produce and has a low power consumption, however, it isn't nearly as sensitive to lighting and contrasts in brightness and colors. The DSLR has a 10.2 megapixel CCD sensor. They are more expensive and less efficient but do better with contrast and are more sensitive. The difference is most notable in pictures with very dim lighting. This also has to do with a larger aperture on the DSLR too. The bigger the aperture, the more light that is able to come in.

    Lastly, there is a large discrepancy in pixel size. Contrary to popular belief, the amount of pixels doesn't really matter after you get above 8 megapixels because we cannot develop pictures and display pictures where anything past that would make a difference, unless you are printing a giant picture, which would be doubtful. Pixel size makes deeper colors and makes the camera able to display more contrast. The bigger the pixel size, the more photons the pixel is able to collect, ultimately leading to a better photo.

    One important note to add is that the processing on the iPhone has gotten very good. Many of the flaws in the camera can be fixed in the post processing. There are many apps and filters and such that can hide and fix any blemishes in photos. All in all, a DSLR is a better camera. It takes better pictures. However, for a phone, an iPhone camera isn't bad. So if you want to take serious pictures or are going on a trip and want clear vivid photos for your memories, a DSLR is the way to go, but for casual pictures, an iPhone will be more than suitable.
  4. DanDuguay
    Many cultures and spiritual factions speak of the importance of frequencies and vibrations. many cultures believe it plays an important role in nature.

    Certain frequencies create geometric shapes

    as the frequency increases, the patterns get more complex.


  5. DanDuguay
    In physics you learn about waves.

    However, many people don't realize that waves are every where.

    A rubens tube is a tube with natural gas pumped through it with holes in the top.

    when a steady vibration is used on the tube, a standing wave is formed. It has nodes and anti nodes like any wave.

    When you put a lot of vibrations through, like say music, the effect is very cool.

    Most rubens tubes are just a linear single tube, in this video however, it goes into 2 dimensions
    the result is amazing.


  6. DanDuguay
    Physics is ever prevalent in the world of sports. Tennis is no exception to that.

    A tennis racquet, much like a baseball bat, has a sweet spot. A tennis racquet however, has 3 so called sweet spots. One is right by the center, and this is a node. A player will feel little to no vibration when the ball is hit in this spot. There is another sweet spot is at the center of percussion. The COM is located shortly below the node. The third spot is located even below that, and it is at this spot where you get the maximum bounce. The force you feel in your hand is due to the vibrations in the racquet so at the node, it makes sense that that is where the sweet spot for most is.

    At the top of a racquet is the dead spot. It is at this spot that the ball barely moves. This is because all the energy from the ball is absorbed by the racquet and doesn't go back to the ball. You can feel, hear, and see when this happens.
  7. DanDuguay
    Destiny is a video game devolved by the company Bungie. Bungie has experience with theoretical physics after they made the Halo series. Destiny is one of the most expensive games ever made, which brings up an important question. Did they do a good job?

    The first thing to look at is the little details. The capes the shadows, the lighting, and so on. In this, in my opinion, they did a good job. The game looks and feels fantastic. There are many flaws with this game, but all in all, they did a good job on the little things. The little physics is easy to miss but helps move the game along seamlessly.

    Another aspect of the game is the sparrow. The sparrow is essentially a hover bike. We do not have one of these yet so I can't say how accurate they were on it. However, it looks and feels exactly how you think one would. It has propulsion on the back. Using Newtons laws it propels itself forward and uses Newtons laws somehow to keep it above the ground.
  8. DanDuguay
    I am a senior in high school. I enjoy physics. These are two facts about me. I have enjoyed math for quite some time now and the application of math is what really draws me to physics.

    I am taking AP Physics C because I enjoy a good challenge. I have a thirst for physics that cannot be quenched by any other class. This class offers a unique opportunity to expand my understanding and increase my skill in physics while at the same time makes me frequently consider my decision to take the class.

    From this class, I hope to gain a solid foundation in physics. Physics will be a major part of my future career and academic ventures, so I want to head in to the future with the tools that will allow me to not only survive, but flourish in my future environments.

    This year I am most excited about working with such an amazing teacher..... bonus points would be appreciated. But in all seriousness, I am excited to expand upon my knowledge of physics as well as learn more about the areas of physics that interest me. I also enjoy labs. Although theoretical physics is all fine and dandy, I really get my kicks from applying what we've learned in labs and experiments, as well as real world examples.

    I am most anxious about the difficulty and the workload. I have never dealt with a load this large and it is frightening to say the least. Not only is it a lot of work, but the work is challenging as well. This makes it rewarding but incredibly difficult as well. But as the ancient Chinese proverb says, "All things are difficult before they are easy".
  9. DanDuguay
    The video below shows a very cool experiment.

    It shows how the flow of water changes when a vibration is applied.

    water reacts very strangely when it is vibrated.

    enjoy


  10. DanDuguay
    The Universe is a fascinating topic. How the universe was made can be traced back to many things, I don't wish to offend anyone, but I will not be talking about any divine powers, just some scientific theories.

    Most Theories start with a big bang of sorts. The big bang is really more of a cosmic stretch of the universe. Most people know about the big bang or at least the basics, so I will proceed to other theories about the origin of the universe.
    The first theory involves another dimension. The idea is that our universe is a 3-D ball bouncing around in a 4-D plane. We are not the only 3-D universe in this plane and these "balls" collide. This collision is a new 'big bang" and the cycle goes on. This would mean that the life of our universe expands and continues until it resets by colliding with another. There are flaws with this theory, like how can the balls be expanding because we know the universe is, what is the limit to the size? Also, it addresses nothing with the 4-D plane, we have no limits for that.


    Another theory is a similar one, dealing with the 4th dimension. This one says that the universe is constantly expanding and in doing so, thins out. The universe is created by the implosion of a 4-D star, and thins in 3-D until it creates the foundation of another universe. This theory explains the expansion and accelerating of the universe but again fails in any justification for it's 4-D claims.

    Lastly is the most abstract theory. This theory doesn't address the creation of the universe but addresses the idea of time itself. It is the idea that there is no past or future just a series of moments. Our perception of time is just the progression of these moments. By this theory, the origin of the universe is irrelevant because time itself doesn't exist, it's just a perceived illusion. I personally don't like this theory because it's impossible to prove, but it makes you think.
  11. DanDuguay
    A fluid that flows past a surface of a body exerts a force on it. Lift is the perpendicular component to the oncoming flow, of this force. It is the opposite of a drag force.

    Aerodynamic lift is different from other kinds of lift. Aerodynamic lift requires relative motion of the fluid. It usually refers to when an object is completely immersed in a fluid.

    Lift is what makes it possible for a plane to fly. Lift is also used in Frisbees. As man takes to the sky, we owe much to the power of lift forces.
  12. DanDuguay
    The bass guitar, or at least the physics behind it, works very similarly to a guitar.

    The note that is produced by plucking the string has to do with the frequency. For example, if a string has a frequency of 440 Hz, than that would be an A note. You can change the octave of the note by either doubling the frequency, or cutting it in half. That means that it is still an A if it has a frequency of 220 Hz or 880 Hz.

    The frequency of the note is determined by a couple of factors. The main factor is the length of the string. When you press down on a fret, you are shortening the length, and in turn raising the frequency. The 12th fret is always an octave up from the open string because its halfway down the string.

    In addition to length, tension plays a role. when you tighten the string you increase the tension and that increases the frequency. The thickness also is a factor, the thicker the string the lower the frequency.

    For more, www.bassplaying.com/physics-off-bass
  13. DanDuguay
    When people think of the light bulb, they just think of Edison. That is not the case.

    in 1802, Humphry Davy created the first electric light. He heated carbon with a battery until it started to glow. This was known as the electric arc lamp. This invention didn't work because it didn't last very long and was just too bright for an practical uses.

    In 1840, Warren de la Rue enclosed a coiled platinum filament in a vacuum tube and passed an electric current through it. The design was based on the fact that the height melting point of platinum would allow it to operate at high temperatures and that the evacuated chamber would contain fewer gas molecules to react with the platinum. Although this was an efficient design, the high cost of platinum prevented it's use in the commercial market.

    In 1850, Joseph Wilson Swan enclosed carbonized paper filaments in an evacuated glass bulb, but the lack of a good vacuum and adequate supply of electricity resulted in an ineffective producer of light.

    There were many variations of a light emitting device before Edison, but he was the first to make a commercially viable model. Since there have been many different models, and there will continue to be changes in the future.
  14. DanDuguay
    Plasma is one of the four states of matter. You have plasma in your light bulbs, TV's, and the sun. Plasma is created by ionization. A gas is heated or put in a magnetic field. Plasma is a good conductor and therefore has a very small electric field.

    Plasma is the most common state of matter in the universe. It is a very important pat in the fusion of light atoms. Plasma is often confined to a small region for fusion to take place in reactors. Plasma is a key part of solving the energy crisis we are facing.

    Plasma is vital to the universe and is very important to us as humans. Plasma is often neglected by most people and that's not fair. Appreciate plasma.
  15. DanDuguay
    Hockey is a fast paced sport full of physics. A prime example is the slap shot.

    The slap shot is basically a large rotational force. The player is rotating his body and uses the stick as essentially an extension of his body. You can calculate the force by finding the impulse on the puck.


    http://www.youtube.com/watch?v=bcielx6_ArQ

    This is a video of Zedeno Chara at the 2012 all star competition

    By simple physics equations, we can find out that his stick is rotation at 12.4 radians per second! That's pretty amazing

    we also can find out that chara was able to bow his stick almost an inch. That creates a huge buildup of potential energy that snaps on the puck causing it to reach these high speeds!
  16. DanDuguay
    A golf swing is much like a slap shot in hockey. A good golf swing is vital in the game of golf.

    A golf swing is almost all rotational energy. A higher velocity means more rotational energy. The more energy in your swing leads to more energy transferred to the golf ball. The more energy you can transfer to ball the farther it will go.

    The angle at which the club hits the ball is also important. You want the face of the club to be completely flat when it comes into contact with the ball. If it makes contact at an angle, it will cause the ball to spin. The spin of the ball causes friction with the air resistance causing the ball to bend, and the ball will slice. This is much like how soccer players are able to bend the balls on shots and free kicks. The club is like the players leg, and the soccer ball is the golf ball.


  17. DanDuguay
    CD's are something that everybody has had or has. But for such a universal product, we really don't know how they work...

    Although the disc looks and feels flat, it actually is quite the contrary. On a CD is a ton of little pits. These pits have binary code in them. Then a Focusing laser goes over the pits, receives the code, and transfers it to a detection circuitry. The digital signal received is then converted to analog form by a D/A converter.

    The Laser used is a semiconductor laser. There are also two prisisms, used in the system that help in the direction of light as well as multiple directions. The direction and the polarity of the laser light has to be manipulated in order to have a properly working system to play a CD.

    As you can see, there is a lot more to a CD than just a spinning disc.
  18. DanDuguay
    In 1936, A British zoologist named James Gray was baffled by the speed of dolphins. These dolphins were able to reach speeds of over 20 miles per hour! He examined the dolphins muscles and demonstrated that they weren't built to reach that kind of acceleration with drag. He chalked that up to their skin and that was the accepted answer..... was.

    It turned out that Gray was wrong. Dolphins are amazing creatures and it turns out, Gray didn't give these water dwelling mammals enough credit!!!! A professor from the Rensselaer School of Engineering, Timothy Wei, proved that dolphins are quit brilliant.

    Wei used technology original used for aerospace research. They tracked two bottlenose dolphins and video recorded them. The video showed the speed and direction of the water behind the dolphins so they could track the force the dolphins applied. It turned out these dolphins could create 200 pounds of force just from tail flapping! TAIL FLAPPING!!!!!!! THAT'S INCREDIBLE!!!!!! Olympic swimmers only generate 60 to 70 pounds of force :'(

    In conclusion, dolphins are freaken awesome. They can generate massive amounts of force with their tails and propel themselves to incredible speeds. So next time you see a dolphin, tell it thanks, thanks for being a dolphin
  19. DanDuguay
    Guitar players have many techniques in their arsenal. A guitar is a very versatile instrument and has the potential to make many different sounds, few more distinct than the pinch harmonic, also known as pick harmonic, or a squealy.

    The basic technique behind it is that right after you hit the string, the string hits your finger. This cancels out the fundamental frequency and all overtones, except those that have a node at that location. Overtones that are a multiple of the intended overtone share the nodes of the lower tones. The Physics behind sound waves is extremely evident in all musical instruments, and pinch harmonics are a great way of manipulating physics in order to create a cool distinct sound that has changed guitar playing.
  20. DanDuguay
    Continuing, another important part of the game is the weaponry.

    To start, there is a weopan class called fusion rifles. The game offers no insight into how these guns work but the only assumption I can draw is that it has something to do with fusion. My theory is that there is some sort of nuclear energy generated by fusion and is somehow controlled and then fired from the wopen. There would be a lot of physics in the charging/splitting of atoms all in a short a series of short bursts.

    There is also less exciting physics. For example there is a ton of projectile motion with the throwing of grenades or bullets. Also their is recoil in the guns. In this game you are a guardian, so I'd assume you are stronger than average but the odds are that there will still be recoil in the gun as a counter reaction of the projectile being launched (unless it's the ACR from MW2).

    All in all, physics wise this is a pretty solid game. However, the story line is very week, the gameplay is repetitive, and the online can be pretty aggravating at times. That being said, Peter Dinklage is one of the voice actors, so you should buy this game.
  21. DanDuguay
    What is a laser you may be asking yourself
    No?
    Understandable, but I will tell you about them regardless
    Laser is an acronym for Light Amplification by Stimulated Emission of Radiation.

    There are many variations of lasers but all have the same core parts. Those Parts are a medium, two mirrors, and an energy source. Energy from the power source excites the electrons in the medium. The excited electrons produce photons of light. There are two mirrors facing each other in a laser. One of the mirrors is completely reflective, the other is only partially reflective. The photons bounce back and forth twixt the mirrors. As a photon hits one of the mirror, it splits and also helps stimulate other electrons. This is called the gain. Naturally however, energy is lost and not all the photons make it to the other mirror. This is called the loss. As long as the gain outnumbers the loss, photons will continue to go through the partially reflective mirror, and those photons is what you see coming out of the lasers.

    There are many different kinds of mediums for lasers. There are dye lasers, gas lasers, crystal lasers and more.

    Also, you can have a lot of fun with laser pointers and diffraction gratings. If I figured out how to post videos on here, I would put a video, but alas, I cannot, so I implore you to explore the mystical youtube in pursuit of cool laser videos. They aren't hard to find.
  22. DanDuguay
    Bowling has been a favorite past time for so many for so long. It is a sport that unites people from all parts of the world. Though the techniques may vary, some more unorthodox then others, some with spin, some with a simple flick of the wrist, the physics behind it is ever present.

    Most standard bowling balls have weights in them, but there are two major types, symmetric and asymmetric. Though they perform very similarly, the asymmetric weights give the bowlers a little more tweak in their shot.

    Getting curve on the ball is an important aspect of the game. This has a lot to do with the angular velocity of the ball. As the ball goes down the lane, the angular velocity changes and in turn, the ball starts to curve due to the force of friction of the ball on the lane

    The difference in the weights has to do with how the axis of rotation goes through the weights. the direction and placement of the axis has to do with the moment of inertia. the different moments of inertia affects how the ball will go down the lane.

    for more http://www.real-world-physics-problems.com/physics-of-bowling.html
  23. DanDuguay
    Acoustic guitars work a lot like electric guitars and basses(see previous blog posts). They have six strings. The note the string plays depends on the frequency. The frequency depends on the length, mass and tension of the string. So that means that you'll have to tune and string your guitar differently depending on what strings you use.

    When you play a note, the strings vibrate and produce a sound. The note produced depends on the frequency. This is pretty much universal in all string instruments. You can alter this by changing the length, so pressing down on the frets, the tension, use the tuning pegs, or the mass, by using a completely different string. I would recommend the first two options and not going to but a new string every time you tune your guitar.

    However, the acoustic guitar has something that an electric guitar doesn't and that's a vibrating top plate. the vibrating top plate creates an air cavity resonance that will amplify the sound of the strings. the vibration of the strings gets to the bridge and the vibration of the bridge is what causes the top plate to vibrate.

    The air cavity resonance can be affected by a lot of factors including the type of wood, as well as the size of the body and the hole. Antonio de Torres Jurado created a style of strutting that has the struts diverge from the sound hole on the top plate, creating a more sustained tone.
  24. DanDuguay
    In Quantum Mechanics, there is a phenomenon called Quantum Tunneling. This is where a particle "tunnels" through a "barrier". I know you're probably saying, Dan! Why should we car about this??? well listen up, and I'll tell you.

    This is important because this explains the nuclear fusion that occurs in the main sequence stars like the sun. Normally nuclear fusion requires a lot of energy to get these particles to collide but quantum tunneling uses a lot less energy. Quantum tunneling is very rare in stars like the sun, but the sun is so massive that the shear number of collisions make quantum tunneling very noticeable.

    If we can find a way to make quantum tunneling much more frequent, we can effectively use nuclear fusion to create energy. This energy from nuclear fusion can help replace our reliance on fossil fuels. There aren't harmful byproducts from nuclear fusion so we can create a substantial amount of energy cleanly and effectively.



    ^^^^That is a good video that helps explain the basics of Quantum Tunneling if you want a visual representation or a different explanation
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