# AlphaGeek

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1. ## Watching light move

I don't even know what to do about that. ... ... *leaves to go post another blog*
2. ## Watching light move

...With the same favorite part. That's scary as heck. TELEPATHY
3. ## Watching light move

You blog posted my last post's topic. Lol. That's saddening.
4. ## Fempto Photography Captures Light in Motion

So far, no other particle has been able to move at the speed of light. However, human beings are capable of seeing light move. Ramesh Raskar and his team at MIT have developed a camera capable of capturing light at 1 trillion frames per second. This method, called fempto photography, can take slow motion videos of light in motion. Watch the video for a better explanation but for those of you in a rush below is a summary of MIT's amazing research. As shown in the video, Raskar uses a laser to send a packet of photons through an object. Using fempto photography, the MIT team created videos of light traveling through a coca cola bottle and washing over a tomato. The group presents promising applications of their technology, such as finding survivors in unsafe conditions or hiding beings as well as exploring inner organs by seeing around corners with light. Perhaps the most interesting aspect of this video is featured in 9:20 - 10:04, in which time appears to be moving in reverse according to the camera's images. How is this possible? Watch to find out! Weird things happen when humans try to go faster than the speed of light Watch Ramesh Raskar's presentation below: http://www.ted.com/talks/ramesh_raskar_a_camera_that_takes_one_trillion_fra mes_per_second.html
5. ## The Physics of Fierljeppen

Haha, awesome! I say we create a school rec. team. Anybody up for some Fierljeppen next weekend?
6. ## Infrasound

Infrasound is sound with a frequency lower than 20 Hz. Human hearing registers sounds from roughly 20 to Hz 20,000, though under certain circumstances the body will hear/feel sound at a lower frequency than 20Hz. Though the human ear does not normally register infrasound, these inaudible waves effect our everyday lives. [ATTACH=CONFIG]530[/ATTACH] In Nature: Infrasound is produced naturally by severe weather and other forms of nature. Storms, thunder, volcanic activity, earthquakes, avalanches, tsunamis, waves, wind, and even the aurora borealis emit these sound waves. (1) Because many animals can detect sounds of lower frequencies than humans, they are able to sense oncoming natural phenomenon. This explains why many animals move to higher ground or act oddly before a storm. Animals also use infrasound to communicate. Whales, hippopotamuses, giraffes, elephants and alligators are among the group that do so. These animals are able to send messages over thousands of miles in this manner. Homing pidgeons and other birds are also able to sense these sounds. They use infrasound in combination with magnetic fields to create a mental map of their surroundings. Human encouters: Infrasound is utilized by humans to locate earthquakes, specific types of rock, petroleum, and even artillery/nuclear weaponry. Low frequencies are also created by man-made objects. These noises are theorized to create disturbances for creatures that can register infrasound. The sounds may cause the animals to become disoriented, causing whales to beach themselves or pidgeons to lose their bearings. (2) Infrasound also causes irritation to human beings. In studies such as that of Professor Richard Wiseman, Richard Lord (acoustic scientist), and Vic Tandy, human exposure to infrasound may increase paranoia, physical discomfort and even nausia. (3)(4) In Tandy's situation, halucinations and supernatural "sightings" were later found to be linked to low frequency readings in the area. Infrasound is also the factor behind mysterious humming, called "The Hum," in certain areas that are audible to some people yet nonexistent to others. The hums are often emitted by man-made or natural sources. For example in Kokomo, Indiana, the humming was later pinpointed in a local factory. A fan producing a 10 Hz noise was the source of the scare. ***Authors note: This post took a little bit more research than usual ^^; It was interesting, though! Enjoy Sources: 1.) http://www-dase.cea.fr/public/dossiers_thematiques/infrasons/description_en.html 2.) http://web.archive.org/web/20041102004955/http://pao.gsfc.nasa.gov/gsfc/educ/science/2000/04-07-00.htm 3.) http://www.msnbc.msn.com/id/3077192/#.UJV9R2-unBY 4.) http://www.coventrytelegraph.net/news/coventry-news/page.cfm?objectid=12722447&method=full&siteid=50003 5.) http://www.theindychannel.com/news/possible-source-found-for-kokomo-hum
7. ## The Physics of Eating Too Much Candy...

Mwahahaha, sugar XD
8. ## Physics and biology collide

So. I was reading my Biology textbook the other day and encountered something called "water potential." A simple summary of this term is water's potential energy , or it's capacity to perform work when free water moves from high water potential to low water potential. What? Physics in biology you say? Of course! :eagerness: Physics is everywhere. Let's define water potential in depth. Water potential is given by the equation water potential (symbol = Greek letter psi) = potential due to solute concentration + potential due to pressure, or: [ATTACH=CONFIG]515[/ATTACH] The potential due to solute concentration, or solute potential, is directly proportional to the number of dissolved solute molecules. Solute binds water therefore reducing the number of free water molecules and decreasing it's capacity to do work. Because of this, solute potential is negative. potential due to pressure, or pressure potential, is the physical pressure on a solution. Tension due to pressure is a negative pressure potential, whereas an applied pressure creates a positive water potential. The biology part of water potential is that it is essential to a cell's well being (plant cells in particular). The water potential determines the direction of movement of water in/out of a cell. For plant cells, it determines the shape and stiffness of the cell. A plant cell is flaccid initially. It becomes turgid when it intakes free water in that the pressure from the water pushes on the cell wall, making the cell swell. The cell becomes plasmolyzed when free water leaves the cell, causing the cell to shrivel and the cell membrane to pull away from the cell wall. This state is dangerous for a plant (commonly known as wilting) and the plant may die. These conditions are created by unequal water potentials of the cell vs the cell's surrounding environment. If a cell has a lower water potential than the surrounding solution, it will intake free water and become turgid. If the cell has a higher water potential than it's surrounding environment, it will expel free water and become plasmolyzed. [ATTACH=CONFIG]516[/ATTACH] If you'd like to know more about water potential, didn't understand a thing I just said or would like background noise doing homework, the following link may be of use to you:
9. ## The Physics of Tom and Jerry

In an episode of Tom and Jerry from 1948, Tom once again has his face smashed in from a falling object. This time, the offender was a half-ounce canary wielding circular cage parts. The bird unfastened the cage bottom and let it drop onto the unsuspecting feline below, making Tom's face into a pancake. How much force does this pan actually make? Could it really damage a cat's face? [ATTACH=CONFIG]513[/ATTACH] First, we must find the velocity of the pan when it hits Tom's face. We know that the pan falls from rest, its acceleration is 9.81 m/s2, and the time it takes to fall from the cage to Tom is roughly 3 seconds (1:09 -1:12 in the youtube video). Using the equation Vf = Vi + at, we find that the velocity of the pan just before it comes into contact with Tom's face is 29.43 m/s. Let's estimate that the pan weighs roughly .1 kg (100 g). Also, let's estimate that the time it takes the plate to go from its initial velocity just before coming into contact with Tom's face and the time when it's final velocity reaches 0 m/s is roughly 1 tenth of a second (.1 s). We know that momentum is conserved in this situation and that (Force)(change in Time) = (mass)(change in velocity). Using this, we know that the change in velocity is -29.43 m/s, so the force of the pan on Tom is roughly 30 newtons. This is equal to roughly 6.7 lb of force. It takes anywhere from 7 to 9 lb of force to break a human nose, so even though it's not likely that the bird cage would've smashed the kitty's face in, he might very well lose his sense of smell. Here's a blast from the past composed of 40 % physics and 60% pain. Disclaimer: I do not promote domestic animal abuse, nor do I reccomend testing 7 lbs of force on your friend's nose. http://www.youtube.com/watch?v=MKyRRP43bh0&feature=related
10. ## Happy Halloween!

[ATTACH=CONFIG]506[/ATTACH][ATTACH=CONFIG]507[/ATTACH] So. I was thinking of what to carve on my pumpkin earlier and thought, "What's something that'll scare the pants off of anyone, even high schoolers?" Bingo, air resistance. Many of us were shaking in our boots when Mr. Fullerton derived a few drag-related equations, but looking back they're not too bad right? Here's a little review. That long page really boils down to a few key equations: Air resistance = Fdrag = bv = cv2 , where b and c are constants VT= (mg)/b V = VT ( 1 - e(-b/m) ) V = (mg/b)( 1 - e(-b/m) ) a = g e(-b/m)t Some equations may contain the variable tau, which looks like a backwards J or a T with a tail. I will use T to represent tau. It is a time constant that can be substituted into the equations above. Tau = T = m/b. I hope that helped a little. Sleep with the lights on tonight, folks. 'Tis the season!

12. ## Hurricanes and Cyclones and Typhoons

Hahaha, pretty much. Very informational and fitting for our rain-day. Love the comic btw
13. ## Trampolines, Energy and Foxes (Oh my!)

Have you ever wondered how trampolines work? Anything fun or worthwhile has physics behind it, so let’s take a peek at the gymnast’s best friend: [ATTACH=CONFIG]497[/ATTACH] I hope you all enjoy my art skills. Read it and weep. :victorious: The magic behind a trampoline can be explained in terms of energy. Let’s say that a child is bouncing up and down on the trampoline. When the child is at a maximum height, his/her potential energy due to gravity is at a maximum. Because PE= mgh, with acceleration due to gravity and mass constant, his/her PE is the greatest because height is at a maximum. However, their kinetic energy is at a minimum of 0 because the child has a velocity of zero and KE= (1/2) m v^2. When the child is in contact with the trampoline and is as low as he/she will travel, his/her PE due to gravity is now at a minimum of zero because the height is zero. However, at this point the child’s kinetic energy is greatest because the velocity at this point is at a maximum. In addition, the potential energy due to the trampoline’s springs is at a maximum. Uspring (potential energy of the spring) is greatest at this point because the displacement x of the spring is greatest at this point and Uspring = (1/2) k x^2. In other words, the spring is at its maximum stretch possible for the child and wants to return to its state of rest, so it sends the child back into the air. If that AP B review didn't click, try watching the specimen V. vulpes exploring this bouncy apparatus. (CAUTION: Video has sound. If you're in the school library, please adjust volume level accordingly before proceeding). Ah, discovery. --'Geek out!

Lol, nice find. Is it me or does this remind anyone of the educational song right before the credits of Bill Nye?
15. ## Why Mumble from Happy Feet stuck to his day job

Many of you are familiar with the children’s movie happy feet, about a whimsical penguin chick that just can’t stop dancing. Why don’t these birds fly instead of dance, you ask? Let’s use physics to figure out why Mumble is aerially challenged: There are four main forces involved in avian air travel: lift, weight, drag, and thrust. As shown by the diagram of a blue jay in flight (credit to http://www.lcse.umn.edu), lift opposes weight and thrust opposes drag. A bird is able to fly when lift is greater that weight and thrust is greater than drag. Read below for more on these forces: 1. Weight: Mass x acceleration due to gravity 2. Lift: This force can be explained using Bernoulli’s principle—as a fluid’s velocity increases, the pressure decreases and vise versa. Bird wings are in an airfoil shape with a bump on the top and a smooth bottom (like an air plane wing). The air is forced to move faster over the top of the wing than on the bottom because it has a longer distance to travel over the bump. Like faster moving fluids, faster moving air causes the pressure on top of the wing to be lower than on the bottom of the wing, allowing the bird to lift upward. 3. Drag: This force is caused by air resistance. The more aerodynamic the flier, the less drag that will act upon the flier. 4. Thrust: This is the force created to push the bird forward. Birds create thrust by the backward push of their wing, like humans do when we push backward with our arms to swim in a pool. Plane propellers and jet engines create thrust for a plane. In short, the reason why Mumble cannot fly is because penguins store fat to keep themselves warm, increasing their weight. Their wings also are not the correct shape or size to produce enough lift to get into the air. Weight > Lift, therefore Mumble dances. Next time, lay off the fish. --AlphaGeek
16. ## Ah the joys of being sick... (Part 2)

Cheers to being sick! The school is like the walking dead, but at least we feel awful together... Yay camaraderie. Thanks for the advice, I'll probably end up with Barrons. And geez, why were you blogging at 6 am? I know you like Physics, but that's pretty extreme. :worked_till_5am: Feel better!
17. ## Relativistic Baseball

"A careful reading of official Major League Baseball Rule 6.08( suggests that in this situation, the batter would be considered 'hit by pitch', and would be eligible to advance to first base." Lol, I suppose that rule is the only thing keeping you from pitching that fast, right Lshads? Nice post
18. ## The Physics of Flipping Cats!

Hahaha 6:10 Fluffy, get in the catipult! Fluffy: Ummm, no. That was really cool, although I think I enjoyed that much more than the cats did.
19. ## Happy New Year!

HAPPY NEW (school) YEAR EVERYBODY!!! I'm super excited for some serious Physics C. Just set up my account! I found this comic online and thought it would be a great way to break the ice: Hee hee. And of course I'll site my oh-so-credible source: http://memebase.cheezburger.com ...Although they did spell cheeseburger wrong. ^-^; And look, I found a fencing smiley face!:fight) --Geek out!
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