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  1. Ever since I was little, I've been interested in thunder and lightning. The lightning would always crack across the sky and that would be followed by a boom of thunder. When i was young, I neve knew why these things happened or anything about sound and light. But now as a student of physics, I know some interesting facts about these occurances.

    Light and sound are both a very big part of our everday life. Without them, life would be very different. Light travels faster than sound. That's why you experience lightning before thunder. Light can travel at about 299792458 meters per second. While sound travels at about 340.29 meters per second. This difference in speed is huge. There is supposedly nothing that can travel faster than light.

    If you put a lamp in a vacumn, you'd still be able to see the light it produces. If you put your iPod in a vacumn and played your favorite song, no sound would be produced. This is because sound cannot travel through a vacumn, but light can.

    To this day I'm still intrigued by thunder and lightning, but knowing the science behind them is pretty cool too.

  2. FaithDemo06
    Latest Entry

    Ah yes, my favorite type of waves. Wi-Fi. Its a beautiful thing, these modulated electromagnetic waves allow you to stream movies and gain access to the internet with out being plugged in. Once only a coffee shop novelty, it can now be found in every house across the country. But how does it work? Wi-Fi can cover as much as an entire school, or building, depending on the frequency of course. Wi-Fi is a type of wave that can penetrate walls and ceilings, as well as cross rivers and high traffic areas. The Wi-Fi signal is composed of large numbers of different frequencies in order to reject noise in any of them. Also certain materials can make it harder for wi-fi to travel, and also other waves (this is the reason for channel settings) can interfere with Wi-fi too.

  3. So far this year, I have to say my favorite lesson this year is went we were working with the machine that shocked us when we touched it. I thought this was enjoyable becaue it was very funny to watch people get shocked when they went to touch or even kiss the Van de Graff Generator. I think the created a very enjoyable setting to learn about how proton, and electrons interact between each other, and what pain they an create when they or not ground. I personally tried touchig the machine and I quickly pulled my hand away because it hurt so bad! But some people were brave enough to go ahead and kiss the thing... I would never. I also found it so fascinating how we all could hold hands as a class and send one huge shock through all of use. I never knew soemthing was possible. But his wwas my favorite demonstration for a class period. I thought it also helped expand my knowledge on how proton, neutrons and electrons interect!

  4. When professional tennis players serve , the ball usually goes anywhere from 120 to 163.4 MPH (fastest recorded in history) which is pretty darn fast. They try to serve the ball as close to the net as they can so their opponent has a harder time of returning it. The closer to the net makes it so the angle to the incident is greater. The bigger the angle of incident is, the closer the ball is to the ground because it is measured against a right angle with the ground. If there is a small angle of incident, that means the ball bounces more vertically and is easier for the opponent to put away and possible smash into your face which is their point. That is why tennis players try to get the ball as close to the net as they can.

  5. So everytime I need to make blog posts I always try to connect what we have been learning in physics to my favorite sport: softball. Now you might think that there are no waves in softball but I am creative and I believe I have found some sort of wave while playing softball. When people throw a softball really high it creates a giant lob that looks like a parabola. And this lob could also look like a half a wave. And if you measured from the ground to where the highest part of the ball reached, you would get the amplitude. But of course, the so called wave would never be finished you would only get to a half a wave and then the ball would hit the ground and die. But today we learned about reflection and could be applied to softball as well. When the ball hits the ground it will be reflected back at the same angle. So I the ball was thrown at a sharp angle measured to the normal line like 70 degrees. The ball would bounce back at that same angle. So while fielding, depending on how the ball hit the ground, you could prepare yourself for where the ball will jump next. Physics can improve your fielding skills.

  6. imani2014
    Latest Entry

    Drifting is when a driver oversteers,or the car exceeds its tire's limits of adhesion, to cause a loss of traction in the rear wheels, when the rear slip angle of a car is greater than the front slip angle. In doing so the front wheels point in the opposite direction of the turn, the car is going left but the wheels are pointed right. Every time we turn a vehicle we resist the change of direction due to Inertia. Simply put, inertia is the amount of resistance to a change in velocity or momentum. Newton's first law of motion connects to this because he said that an object at rest stays at rest or continue with constant velocity unless acted upon by an outside force. So an object will continue as it was unless some external force comes in and messes everything up. Inertia is most often masked by effects of friction and air resistance both decrease speed of moving objects and gravity.The friction between the tires and the road and allow the front wheels to break traction. Turning the steering wheel in the opposite direction, intertia of the car that is trying to slide in the opposite direction is added to the force applied by the engine and the friction of traction between the tires and the road. If the car is front-wheel drive, the rear tires weigh less so they break traction first which causes the rear to slide out. Lifting the throttle makes another weight transfer and enables the rear wheel to weigh even less. Such physics was applied in the movie Fast and Furious: Tokyo Drift. the main character had to master the physics of drifting to beat the antagonist. This called from some amazing racing/drifting scenes. Physics is everywhere whether we acknowledge it or not. But be careful when trying to drift - no saying that you should try, honestly I can't stop you- if the center of gravity is too high you will roll over instead of sliding.

    Drifting scene from Fast and Furious: Tokyo Drift :

    Learn to drift:

  7. A roller coaster typically begins with a chain and motor exerting a force on the cars to lift the train to the top of the first hill of the ride, which is also the tallest. Once the train makes it to the top and is pushed over the top of the hill, gravity takes over and it becomes an experience of energy transformation.

    At the top of the hill, the cars possess a large sum of potential energy. That potential energy is equal to the mass and height of that object. After the first drop the cars lose a lot of this potential energy because of the loss of height, but they gain Kinetic energy, the energy of motion. Kinetic energy is equal to the mass and velocity of the object. So throughout the ride the initial Potential energy is just lost then gained, lost then gained until the end of the ride.

    Below is the worlds tallest roller coaster, The King da-ka, located at Six Flags Great Adventure in NJ. With a height of 139m. At launch you are traveling at 206km/h. Only 10 Km/h less than a Cessna 182, a single propeller airplane.

  8. The moon does some strange things if you haven't noticed! And something very strange is happening this Saturday, April 4th! A so called, "Blood Moon", is to occur that will be the shortest of the century, these are very rare occurrences that are very interesting to examine.

    The blood moon occurs only when the sun, moon and earth are lined up perfectly with the earth in the middle. The earth as it lines up with the sun casts a large shadow which then envelopes the moon as it passes into the earths shadow. As it does this the moon becomes darker and eventually a reddish hue. The moon is turning red for a certain reason because the atmosphere of the earth filters out the blue light of the sun leaving only the red light to shine on the moon giving it it's signature red moon color.

    This blood moon occurrence happens to be a special one though, that is because usually a blood moon occurs twice a year, but when it occurs four times, like it will this year, it is known as a tetrad.

    So if a blood moon is when the moon is blood red, a blue moon is when the moon is blue right? Surprisingly no! A blue moon has nothing to do with the color of the moon unlike the blood moon. So what is a blue moon? Well it is a confusing tail.

    Originally the idea was traced to the "Maine Farmers's Almanac", which stated a blue moon was the third full moon in a season that contains four full moons instead of three which is a rare occurrence. But the idea was misinterpreted by another author who stated a blue moon is the second full moon in a month with two full moons, this was published and adopted as common knowledge.

    Now when you're friends start talking about the lunar cycles at the lunch table you can contribute useful information into the conversation. Enjoy your Saturday night which I'm sure you'll spend doing something other than watching the moon!

    Blue moon information from space.com

    Picture from toonpool.com

  9. A video combining the amazing lectures, clips and television shows of some of the most famous celebrities and scientists on the planet. Combine it with music and you get the best thing ever.

    http://vimeo.com/29466108

  10. IVIR
    Latest Entry

    This past weekend, I saw a giant game of Jenga at MIT. Literally. The blocks were nearly 2x4s, and the structure was taller than I am. While I did not stay to watch, it is interesting to think about a few of the different strategies that I remember from my childhood days. First of all, I used to believe that the faster you pulled the object out, the less chance a collapse would occur. While I'm not sure of my logic behind this reasoning, I most likely imagined that hopefully the structure just wouldn't have time to collapse if I pulled it fast enough (Yeah, I know). However, after the block is removed, whether quick or slow, the structure will still have the exact same properties regardless of speed. Another theory may be to reduce friction, but it is important to note that the frictional force does not rely on velocity, it relies on the normal force. The one factor that does effect the result of the turn is how straight you are able to pull the block out. By pulling the block straight out, you are minimizing the normal force, but if you tilt to one side or another, you are increasing the normal force and creating a larger frictional force. 

    Another concept of the game Jenga is torque. Since torque is F x r and the r in most jenga games is relatively small, the structure can often withstand the removal of blocks that may have seemed impossible. The middle block is at the center of the fulcrum, so the r would be 0, allowing players to theoretically remove all of the outside blocks while keeping a cross pattern in the middle. This is much easier said than done due to the friction caused by uneven pulls (an even perfect pulls as the wood has a large surface area) and the fact that even a small breeze can cause enough torque in the other direction to knock the tower down. A horizontal breeze may have a small force, but since the center point is technically the ground in this plane, the r would be as tall as the tower. 

    Hopefully, the physics of Jenga could help people improve their gameplay, but to be honest, isn't the best part watching it all fall? 

     

  11. As someone who is extremely afraid of heights, it is highly unlikely that I will ever go skydiving. However, that doesn't mean I can't appreciate the physics of it. For instance, skydivers accelerate when they go down because the force of gravity is greater than the drag on their bodies. Also, the acceleration in question will always be 9.81 m/s^2 as that is the acceleration due to gravity. But when the parachute is opened, the increase in surface area creates an increase in drag, therefore making the skydiver slow down.

  12. The gold foil experiment is the famous experiment conducted by Ernest Rutherford that we all learned about in chemistry class. This experiment proved that atoms are made up of mostly empty space. In fact 99.9999% of an atom was proven in this experiment to be empty space. Lets say we could eliminate all that empty space by condensing the parts of an atom together. How much weight could we fit in a small space such as a single teaspoon? Over a billion tons! 

    This idea is common when studying astronomy. At the end of a stars life, it collapses and explodes in a supernova explosion. The remaining mass that the supernova leaves over is so dense that the star begins to collapse in on itself. As a result of this, electrons fall into the nucleus and smash into protons becoming neutrons; hence the name neutron star.

    This animation shows a star going through a supernova explosion. The accuracy of this animation is highly questionable but it certainly looks cool.

    giphy.gif

    image.png

  13. the Doppler effect is when the frequency of a sound wave becomes higher the closer you get to it and then the pitch lowers as it passes you again. when an ambulance is speeding down the street with its sirens on the pitch of the siren changes as it passes you. when it is coming towards you its pitch and frequency start to increase and then reach a maximum as the ambulance is right next to you. then as it drives passed you again the pitch and frequency of the siren lowers the farther and farther away it gets from you. the Doppler effect is the difference in frequency and pitch the siren makes as it passes you.

  14. Water skiing involves many different components of physics. The fundamentals of it are based mainly on angles and gravity. When you are trying to get up, you have to make sure you keep your ski at a certain angle so that the water pushes down on the ski, creating a downward force that enables you to stand up. Once the force of the water pushing up on the ski is equal to the force of gravity pulling down on the ski, you are able to stay on top of the water.

    Tension is also involved in water skiing because the rope from the boat to your hand pulls tightly, creating tension. When the tension in the rope is constant, you will be traveling at the same speed as the boat pulling you. However, since the rope from the boat to the water skier keeps you moving in a circular path. Since you are moving in a circular path, there is also centripetal force. When the centripetal force is high, the water skier may be moving faster than the boat itself.

  15. Lots of people have heard the word “superconductor.” But, not too many people really know what they are or how they’re made.

    A superconductor is an occurrence of exactly 0 internal resistance to electrical charges and the removal of interior magnetic fields, known as the Meissner Effect. During this change, all magnetic flux within the material is transferred to the outside, greatly multiplying the outside field. Super conductance was discovered in 1911 by Dutch physicist Heike Kamerlingh Onnes. And, it’s actually a phenomenon of quantum mechanics.

    Superconductors are made when a material is cooled to below that material’s critical temperature. And, they can break down once the magnetic field around them grows too great as well. There are currently two classes of superconductor based on how they break down. Type I superconductors abruptly stop conducting in this way if the field breaches a certain threshold value. Type II superconductors begin to accept magnetic flux back into the material above the threshold point, but retain their 0 resistivity. It is because of these quirky effects that superconductors cannot simply be seen as perfect, or ideal, conductors, but rather entirely separate phenomena.

    Scientists still study superconductors and their applications in depth today. In 1986 ceramic materials were shown to have very high critical temperatures, ones that were theoretically impossible, and were dubbed high-temperature superconductors.

    Nowadays superconductors are used in particle accelerators and mass spectrometers due to their incredible power as electromagnets. However, they have all kinds of fascinating circuitry and quantum mechanics applications. Feel free to investigate yourself, but for now, enjoy a video of a superconductor floating above a magnet, known as quantum levitation.

     

     

     

  16. When I sit on my couch and watch television (Netflix), there is a lot of physics involved. For example, I do not do any work, because I stay in the same place for hours. Sometimes I get up to go to the kitchen for food, but then I go back to the couch, so my displacement is zero. Also, sound waves, which are mechanical and longitudinal, travel from the television to my ears, which are about ten feet away from each other.

  17. Football seems pretty stupid to me. Athletes line up across from eachother, then run at eachother as fast as they can. However, football is my favorite sport to watch. There is alot of large forces coliding in football. Every colision can be related back to physics. The force of anything is determind by its mass and acceleration. The larger the mass of an athlete and the more acceleration an athelete has the larger the force the athlete can produce. NFL players can produce large forces on eachother. This leads to big hits and head injuries.

  18. When light is hitting you it is actually waves or particles of matter. This is because light is matter and light is waves.

    Young's double slit experiment is what can prove light is a wave. He projected light through walls with two narrow slits in them. The result on the wall behind is interference patterns which shows that when the waves of light go through the slits they interfere and cross each other. This also shows diffraction which is the bending of waves around obstacles or spreading of waves when they pass through an opening. Another thing that proves light is a wave is red and blue shifts. When a star is moving very quickly at us it appears to us bluer than it actually is because the wavelength decreases.

    The Compton effect proved that light is a particle because it shows that light has momentum.The photo electric effect is when light is shined at a thin piece of metal the photons knock electrons out of the metal. This shows that electrons are pieces of matter because they have momentum.

  19. In my previous blog post, I discussed the overall interface you'll be using in Kerbal Space Program. If you don't know what you're doing, I recommend reading that first before continuing on with this post.

    Before I even start with actual designs of rockets, I'm going to teach you how to build quickly and efficiently.

    To start, you'll need to place down a part. Keep in mind that the first part you place down is the part you're going to have to build off of. Whenever you pick up this part, you will pick up your entire rocket. Whenever you pick up a part connected to this part, it will pick up every part placed on that part, excluding the first part. Now that you understand that, you're going to need to know how to move around effectively.

    By holding right-click, you can rotate around a certain point on the center axis of your rocket. By using the scroll wheel, you can move vertically up and down. By holding Shift and using the scroll wheel, you will move closer to and farther from the center axis of your rocket (Alternatively, you could do this by holding down the middle-mouse button and moving your mouse up/down).

    When building a ship, 

    Now we can get into some design basics.

    There's a lot of things to take into account when designing a rocket, even in a video game.

    Always remember to take aerodynamics into account. You can't just launch anything through the atmosphere at well over the speed of sound and expect it to be fine. Take the following, for example.

    image.png.c0cc7c9fa4d94772acce45d61b5c3053.png

    This is a simple landing can with some batteries, retractable solar panels, RCS fuel tanks, and an antenna. If you launched this through the atmosphere, something could very easily break, especially if you used the unprotected versions of the solar panels, or, lord forbid, you extended them. But then how would you get this into space? Well, there's many solutions, such as trying to fit it all inside of a cargo container, or you could make a column of octagonal struts and strap the bits onto that.

    There is also one other thing in the game you can use, and it's quite stylish. First, you'd have to disconnect the entire top piece from the landing capsule, and place an "Airstream Protective Shell" on top of the capsule. When you first place it, it'll start dragging a frame with your cursor, but just right-click to temporarily remove it. Then, re-place the top piece on top of the Protective Shell part. Here's where things get interesting. Right click on the Protective Shell part, and click "Build Fairing" as shown below, then drag the frame up along your top piece, and click when you want to start to drag it in. You can use the other picture below as reference.

    image.png.8e6c4f9da2c5e9483fb7854336e3f14c.pngimage.png.158d6c3a290397d4b37bb3b8c99302a3.png

    This fairing can be ejected as part of a stage when you leave the atmosphere, so the craft on the left will look like the craft on the right. Just be careful with your design for when you do eject it, because it shoots sideways.

    Here's another aerodynamics example:

    image.png.a8c19b615e787d19d1d69121f800a272.png

    This rocket will fly. But after a little bit, it will start to flip out of control, and plummet into the ground. But why? If you build a ship like this and deviate from being normal to the ground by even the slightest amount, air resistance kicks in, and your rocket will flip upside-down. So how do you avoid this? Simple: Add some wings. Two could work, but you should add more, just to be safe.

    Another thing commonly done in KSP is when people add tons of fuel to their spacecraft, and then is surprised when they can barely get into orbit. Keep in mind that adding more fuel does let you burn longer, but also increases the weight of your rocket. Your thrusters will always put out a certain amount of force, and if you just add more fuel to your craft, you might end up with less delta-v than you started out with. We all took Mechanics, so you should know that net force is equal to mass times acceleration, so if mass goes up but force stays constant, acceleration must go down.

    Some other things to think about include:

    - Do you need extra power?

    - Do you need power generation?

    - Do you need heat reduction?

    - Do you need a ladder for your Kerbal?

    - Do you have a heat shield?

    - Does it look nice?

    - Is it powerful enough to get you where you need to go?

    - Does it weigh too much?

    - Do you have enough parachutes?

    - Should you add high-altitude parachutes?

    And, most importantly, something forgotten in the following picture.

    image.thumb.png.5d6b0ea2d2aa131a3c75a705aabdf76e.png

    Yes, there are no wings, and it is hideous, but those aren't the biggest faults with the spacecraft.

    If you look on the bottom left, it shows the staging. Every time you press the spacebar, you begin the next stage. In this case, the first stage would start the first thruster, but would also trigger the decoupler, disconnecting the main booster from the rest of the rocket. Now look at the final stage. When triggering the last decoupler to expose the heat shield for re-entry, it would also trigger the parachute, rendering it useless, and dooming poor Jebediah to crash into the planet.

    Even if your design is perfect, one simple mistake in the staging could ruin everything when you least expect it, so always remember to check it before you wreck it.

    In my next blog post, I'm going to discuss simple flight controls and methods.

  20. isaacgagarinas
    Latest Entry

    When I was in Jacksonville I went to a go kart place called the Autobahn Indoor Speedway. These weren't your typical go karts however. At the Autobahn the cars reached speeds up to 50 mph! Drivers have to wear helmets for safety and the speed made for some pretty intense races. There was a lot of physics involved in driving the cars. One of the most important parts of learning how to be as fast as possible was getting used to knowing how much and when to brake around turns. Braking too much will slow you down and can cause wrecks, however not braking enough can cause you to slam your car into the wall, also slowing you down and putting you at risk of wrecks. The only way to do this was through friction. By stopping the rotation of the wheels the tires then grinded against the concrete ground creating friction which is what would slow down your car. Also many forces were exerted with the bumping of cars and from running into walls. If my car ever rammed into another, the force exerted from my car onto his was the same amount of force his exerted onto mine. A lot of centripetal acceleration also takes place at all 4 of my wheels. Even if my car is moving at a constant velocity, the wheels are constantly changing direction as they spin and therefore accelerating inward. Finally the force of gravity is always constant on me and my car. Gravity exerts a force of 9.81 m/s^2, which is what keeps me and my car from flying off of the track. The Autobahn Indoor Speedway was a pretty intense go karting place and I had a lot of fun racing!

  21. Working out is the act of building mucsle and exercising your body. In preforming acts of runnig lifting or endurance, you engage in a variety of physics topics including friction, resistence, energy, forces and momentum.

    For working out, the act of building mucsle demonstrates an example of resistance and or friction. When lifting heavy objects or moving in a forceful manor, it requires you to condemn in motion that essentialy tears the musles cause the force required is working out your mucsles and you gain strength when they grow back allowing you to deliver a greater force.

    In terms of energy, chemical energy is converted, therefor conserved and then transfered to the body in a new form of mechanical energy which allows you to move things and or run and exercise to get in shape. Continueing to expell energy requires more energy to keep up your endurance and allowing maximum potential to work out. By having stored energy or potential enrgy, you have the ability to move and then its transfered to kinetic energy in your work out secssion.

    In terms of momentum, bigger and more heavy objects when being lifted contribute a greater momentum against your body inhibiting a greater level or degree of diffuculty for bigger objects and will make more of an impact for you. Because of the more intensive strain it provides. Lesser momentum makes it easier to life and "no pain no gain" implies you will not see great results.

    Working out is an action that delivers wide diverse physics topics which are good to understand so you know what is happennning to yourself durring work outs.

  22. etracey99
    Latest Entry

    Many of us know the Aurora Borealis as the 'Northern Lights'. This natural phenomenon is, of course, thanks to the physics of our Earth and its atmosphere!

    Topic of the moment - northern lights and solar wind(Photo credit: NASA)

    The Aurora Borealis is an extremely beautiful event that occurs most often close to the magnetic poles of Earth. It occurs due to charged particles coming from the Sun of which collide with other molecules found in the Earth's atmosphere. Solar winds from the Sun carry these charged particles and when the wind passes by Earth, particles may be trapped in the atmosphere from the Earth's magnetic fields! The charged particles ionize molecules in the atmosphere, which give off light. This creates the Aurora Borealis!

    I had previously thought that the Northern Lights were from light reflecting somehow, but it awesome to see that it is caused by magnetism, which fits into our past few units very nicely.

  23. jwdiehl88
    Latest Entry

    A simple snap-back mousetrap is a clever machine. With just a few parts (a wooden base, a spring, a metal bar, and a trigger mechanism) it can do its job quickly and efficiently.  When a mousetrap is set, the spring in the center is compressed, becoming a source full of potential energy. This energy is being stored, not used, but as soon as the trap is released, it is converted to kinetic energy (the energy of motion) that propels the snapper arm forward.  This is a perfect example of conservation of energy.  It takes an amount of force to set the mousetrap and when the trap is triggered, it creates a force onto the mouse that triggered it.  

    the levers of a mousetrap

  24. Hey Mr. Fullerton and anyone whos reading this, its been a pleasure grinding this year. Hope you enjoy this great video and maybe even chuckle a bit. 

     

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