This Thursday, the Irondequoit High School Philharmonic Orchestra and Choirs will be performing their major works concert at the St. Mary's Church, right next to the Geva theater. It's quite the interesting concert to perform, in that we're all playing in an unfamiliar venue, and have had only a single day where we ALL got together to practice. Oh, and it doesn't help that the acoustics in the church are terrible, arguably only a little better than the IHS gymnasium.
Why are they terrible, you ask? Let me tell you. In a real theater or concert hall, the entire venue is designed with the acoustics in mind. For simplicity's sake, imagine sound waves as transverse instead of longitudinal. As Physics 1 taught us, if there's more than one source of sound, the sound will be amplified where peak meets peak and trough meets trough, and nullified where trough meets peak. Because the architects who designed the building know, in general, where the performers will be, they'll have a good idea of where the sound will be loudest (likes meet), and quietest (opposites meet), and will thus place the aisles at quiet points and the seats in louder areas, to maximize the enjoy-ability of the performance. Churches, however, (like St. Mary's) are not designed with acoustics in mind. Churches are designed for masses in which they generally have only a single person speaking, meaning that even if sound reflects off the walls, there's generally going to be a pretty similar listening experience everywhere. As such, the seats are organized in straight rows which are evenly spaced, meaning that when the orchestra starts playing, there's going to be some odd spots in which the sound dwindles more. Add to that the cramped feel of squeezing an ~20 person orchestra and ~50 person choir onto and in front of an altar, and it makes for a really interesting performance.
I recently found an online play-through of a game called OneShot, a fourth wall breaking game in which the main character, Niko, has to restore the sun (just a giant lightbulb) to a world in which the previous sun died out with the help of the player, who acts as a... far from omniscient god of the world that can't directly interact with anything and can only be heard by Niko. Throughout the game, characters reference a material called phosphor, which they say gives off the power of their previous sun, and is used to provide light, generate power, and grow plants.
While bored, I decided to do a quick google search for phosphor, and it turns out it's actually a real thing, although it doesn't function as it does in the game. In real life, phosphor is a luminescent material used to coat various lights in order to change the color that they emit, with the simplest example being LEDs. For example, most white LED lights actually utilize a blue light to generate their light. How does the light become white then? The answer is that there's a phosphor coating around the light which absorbs light at the blue wavelength, and re-emits light at longer wavelengths, resulting in a full spectrum of visible light instead of a single color. And it should be noted that phosphor isn't a single compound, however, but an entire category of compounds. By changing which compound is used, as well as its density, its possible to achieve a variety of affects from simple lighting to creation of glow-in-the dark materials.
Ever heard a song or some other set of sounds and thought you could make out some sound or phrase that, on close examination, wasn't really there? I'm not talking about misheard lyrics, but lyrics that didn't even exist at a point in a song. Well there's a reason for that. The reason is that, due to the way the song is layered, a specific set of frequencies that the song's instruments play is close enough to the set of frequencies that would be heard if a human were talking, that the brain can perceive it as such.
Don't believe me? Here's a video of various songs broken up into sets of notes based on the frequencies in their audio files, and then played solely on a virtual piano. There is no other instrument being played here, simply a piano. See how much if it you can make out:
No, the video doesn't just consist of All Star, but it is a common enough song that you should be able to pick out at least some of the lyrics. So, why exactly does this work?
As a human speaks, the frequency of their voice changes in order to create the sounds of various sets of letters. At the same time, their voice cuts in and out, also to get the proper sounds of the syllables being said, to make it more smooth. By copying these frequencies precisely at the precise times they occur, it's possible to use any instrument in order to simulate human speech patterns, thus creating the illusion of a voice being heard.
This not enough to convince you that a computer could mimic a human voice? Look up a video of a neural network analyzing human speech. It can actually get pretty freaky to listen to.
Over the weekend, I finally watched Disney's Moana (it's been out for what, almost half a year?), and let me say I thoroughly enjoyed it. It was just the right combination of funny, dramatic, and the Rock singing to keep me in my seat for a solid hour and a half. Now, being Disney, I'm not even going to pretend that physics makes sense (how does the water move like it's alive? is it possible to have a giant air pocket directly underneath water? how is matter conserved when Maoi transforms?), but one part of the film particularly set off my physics sensors, and that was when Maoi was singing about his many accomplishments as a demigod. He stated that he "lassoed the sun," giving the people of Moana's earth longer days, and implying that he pulled the sun closer to the earth. Now, ignoring the fact that the sun is a giant fusion reactor and anything that came into contact with it would almost immediately burn up, I wanted to find out if pulling the sun closer to the earth would actually increase the length of the day.
Now, in order to make this simple, I'm going to make two assumptions. The first is that Moana's earth follows a geocentric model, that way the sun's movement will actually affect day length instead of year length, and the other is that the sun orbits Moana's earth in a perfect circle. Obviously this isn't true in reality, but it makes the math easier. So, being the sun follows uniform circular motion around the earth, Fc=Fg, meaning mv2/r=GMm/r2, where m is the mass of the sun, and M is the mass of the earth, and r is the distance between them. Simplifying and solving for v, we get v=(GM/r)1/2. Of course, this tells us nothing about the period of revolution. In uniform circular motion, the period T=2πr/v, and substituting in our previous equation, we find that the period of revolution, as a function of the radius (everything else is constant) T=2πr3/2/(GM)1/2. This means that as the radius increases, the period increases, and, more importantly, as the radius decreases, so does the period. Being our period of revolution in a geocentric model is equal to the day length, this means that Maoi pulling the sun closer should have decreased the length of a day, not increased.
For anybody not familiar with Boyle's Flask, it's a reservoir of water connected at the bottom to a tube such that the water infinitely pours into itself. Essentially, perpetual motion. And it's only a theoretical concept.
With that in mind, watch this quick video:
Done? OK, now, can you tell me what the video did wrong?
If you answered used an obscure method to trick the viewer into thinking it actually worked, you're 100% correct. Based on a few other videos which debunk the scam, fluid dynamics don't work like that, even for a carbonated beverage. When put into an actual constructed Boyle's Flask, without a hidden motor, liquids, even carbonated ones, will eventually reach an equilibrium point where the surfaces of both liquids are at the same height, WITHOUT pouring back into the flask. Even if the liquid is drawn out so that it reaches the end of the tube, instead of flowing down into the flask, the difference in pressure will actually pull the liquid back through the tube until it reaches dynamic equilibrium once again. Of course, this isn't saying perpetual motion is impossible, but it is saying that this specific instance has been largely disproved by actual science.
One of my favorite games that I've found recently is Starbound. It's a 2D sandbox game revolving around travelling through space to fight off a threat which seeks to destroy all life in the universe. I've built countless bases and colonies on planets which range from a perpetual tundra to a giant magma ocean, and I love it. But there is one thing that's always bothered me.
Gravity. And not because they got it wrong, but because they got it half right. The developers included planets of varying sizes, and, in game, larger planets have a higher mass and gravity, and the force of gravity decreases as you move farther from the surface. However, one thing the developers didn't implement (aside from low gravity on your ship, which isn't even spinning to simulate gravity) is the difference in gravity as you move towards the center of the planet. You know the equation for gravity, right? F = GM1M2/r2, right? Well, that only applies outside an object. Inside an object, gravity is actually linearly proportional to your radial distance from the center, meaning it decreases as you go further in, at least if you assume density as a constant.
But in Starbound, gravity doesn't change at all as you go further down. As a matter of fact, from hours of play time, it seems as though gravity near the core of a planet is the same as gravity at the surface. It may just be me on this, but it really bugs me that the developers didn't even implement the (wrong) assumption that gravity would increase near the core, instead opting for a simpler approach to gravity. Granted, it did make getting out of the planet a lot easier...
More Rick and Morty! This time, I'm talking about the episode where Rick and his son in law, Jerry, are trapped in a simulation inside a simulation inside a simulation (no, that's not a typo) by a species of space pirates who are out to get Rick's recipe for concentrated dark matter, which he uses for intergalactic space travel. By the end of the episode, Rick tricks them into blowing themselves up by convincing them that the recipe involves, "2 parts plutonic quarks, 1 part cesium, then add water."
Anybody who knows anything about atomic metals will recognize cesium as an alkaline metal which... doesn't exactly get along well with water. Simply put, by combining alkaline metals and water, you can create a small explosion. And I mean small. While some TV shows will show insane explosions resulting from mixing the two, it takes an insane amount of metal to actually cause serious damage. Presumably the "plutonic quarks" are some sci-fi way of amplifying the explosion, but I'm not going to dwell on that too much.
Why do I keep messing with relative size today? It's starting to get weird.
Anyways, I was recently suckered in to watching the entirety of Rick and Morty, a sci-fi show about a kid and his alcoholic mad scientist grandfather who travel to various parallel universes causing all sorts of dark comedy along the way.
For example, the time when Rick created an entire miniature universe in a box in order to sucker the intelligent life inside into providing power for his spaceship/car. Then, when the battery stopped providing power, he and Morty went inside the "microverse" to find one of the scientists had created a "miniverse" which exactly paralleled what Rick had done (except to power the entire planet). They then went inside the "miniverse" to find a scientist who was beginning work on a "tinyverse" (I'm not re-explaining the joke), and go inside the "tinyverse," but get trapped when the "miniverse" scientist blows up the only way out with himself in it (it makes a lot of sense in context).
My only problem with this is that the show treats each layer down not like a parallel universe, but like it ACTUALLY exists inside the box, implying that everything is scaled way down. This would imply that, just based on the size of the battery compared to that of a UNIVERSE, Rick and Morty would be smaller than quarks by the time they entered the microverse, let alone how small they are in the tinyverse. Similar to Antman, this would create a black hole, or at least mean that Rick's car is being powered by one.
Granted, the show takes extreme liberties with physics for the sake of comedy, more of which I'll talk about in a separate post.
Similar to Wailord from the last post, there are other ridiculously disproportionate Pokemon. Although it has a bit of an excuse as being from a world where physics as the Pokemon's world knows them don't really apply, Cosmoem takes the cake as being both the heaviest AND smallest Pokemon, coming in at 999.9 kg and .1 m (roughly a ton and 4"). Given that it's design is essentially a perfect sphere surrounded by several flat plates, to make calculations simple, I'm going to assume the vast majority of its mass is in the spherical portion of the design, which is about half the total height. This gives Cosmoem an estimated mass (in the sphere) of 6.5x10-5 m3, and a density of approximately 15.4 million kg/m3.
Lets compare this to a black hole. Using its Schwarzschild radius (or Event Horizon) to calculate it's volume, it's possible to get an approximate density of a black hole. Borrowing somebody else's calculations for a galaxy sized black hole, the approximate density is 200 kg/m3. This would imply that Cosmoem is, in one vein of thought, a self contained black hole, considering there are no known objects in nature that can achieve a density that high aside from aforementioned black holes.
As a final thought, let me also mention that there is no way Lillie should have been able to pick Cosmoem up in game, and that's just from a weight perspective.
Many people understand that game designers take certain liberties with physics in video games. It makes the games more fun to play, especially when it's the difference between jumping off a cliff and either rolling to inexplicably survive, or dying due to a ton of fall damage. Or the difference between having an awesome volcano map and burning up the moment you set foot within a few meters of lava. No, wait, magma, lava is outside the earth's surface. But, you get the picture.
Of course, when the mechanics in question have NO AFFECT whatsoever on the game play, designers have no excuse.
Take a look at Wailord, a Pokemon based on the blue whale, for example. In game, Wailord is listed as having a weight of 877.4 lbs (398 kg), and a height of 47'7" (14.5 m), being one of the heaviest and largest Pokemon in the game. Ignoring the fact that Wailord and other 'mons can survive outside of water, however, can bring about an almost paradoxical revelation: the fact that Wailord seemingly floats above the ground in battle both does and doesn't go against the laws of physics. The reason? Wailord is actually less dense than air, meaning it should not only float, but float out of the troposphere.
Want proof? Based on Wailord's in game model, it is approximately six times as long as it is tall, giving it an approximate length of 58 m. It is also almost perfectly round, meaning it has a depth of about 14.5 m. Given Wailord's shape, a cylinder with two half spheres on either end, it has an approximate volume of 8779.4 m3. Knowing that density = mass / volume, it's possible to calculate Wailord's approximate density as being .045 kg/m3. A quick google search reveals air's density to be 1.225 kg/m3. Even halving his estimated length doesn't help much, only increasing his density to about double the current, which is still well below air's density. Considering that less dense objects tend to float above more dense objects, this would mean Wailord should be floating well out of range of whatever battle its trainer sent it out into.
While it might not be a major pastime for me, I enjoy learning about magic. Not of the satanic ritual variety, but of the slight of hand, stage/street variety. Sometimes I like to use this to harass my friends with impossible tricks, other times I just do it to practice some fine technical skills. In this case, namely how to throw playing cards.
If you have a deck, go grab it right now, and try to throw a card. Watch, as it flops to the ground like a piece of paper. Now, grab it by the corner, and try throwing it like a frisbee. Suddenly, the card will move in a straight line or arc, and, depending on what you're throwing it at, lodge itself in its target. Why does this change in motion change the outcome of the throw? To explain it simply, by spinning the card, the angular momentum of the card prevents it from being easily rotated in another direction. Combine it with the low air resistance that you create on the card's edge when throwing it in such a manner, and the air resistance prevents the card from actually fluttering down like it would if not spinning.
While I'm on the topic, let me mention that, while it could stick in the right target, a playing card CANNOT be used as a weapon. Due to its relatively low mass, it would lack the sufficient energy necessary to cause more than a small paper cut to the human body. If you don't want to believe me, however, know that this myth was tested by the MythBusters, and a card launched at 150 mph by a machine didn't have enough energy to cause more than said paper cut.
The Phoenix Wright: Ace Attorney series is one of my personal favorite sets of logic/puzzle games of all time. Going through the cases one by one, you begin to feel like a real Sherlock Holmes... if Sherlock made wild accusations in order to buy a little time to find proper evidence which may or may not actually support them. And if Sherlock Holmes involved a bunch of quirky witnesses and pop culture references. And if Sherlock Holmes took place in a universe where California and Japan are somehow the same thing. And if... well, you get the picture. Being one of my favorite games, however, does not excuse it from defying the laws of physics.
The specific instance I refer to (being the game includes ghostly possession which transforms the channeller's body into that of the spirit and telekinetic lifting of rubble which came from absolutely nowhere) occurs during the first case of the fourth game. In this case, the victim was murdered with a glass grape juice bottle (not actually a censor for wine, as cases in later games both include alcohol and outright confirm that the grape juice is of the "non-fermented" variety), resulting in death via cerebral hemorrhaging due to blunt force trauma to the forehead. All well and dandy, right? Except that the bottle was both fully intact and fully empty. So, I got to wondering if this were actually possible, when I found the results from an old MythBusters episode where they tested something pretty similar. They wanted to know if a full or empty bottle would cause more damage to the human skull. To sum up their results, the empty bottle generated less G-force during an impact (28.1 G as opposed to 22.7 G, natural, as it weighs less), could not break a simulated human skull, and DEFINITELY broke when smashed against the simulated head.
While the in game autopsy confirms the cause of death, this creates a contradiction with real life physics. Either the bottle wasn't hit hard enough to break, and therefore shouldn't have caused blunt force trauma, or the bottle was hit hard enough to cause blunt force trauma, and therefore should have broken. While this can likely be attributed to a different makeup of the structure of the glass, I'd be more inclined to believe that this was done due to necessity, as the position of the defendant's fingerprints proves integral in the trial, which means a broken bottle would make certain things much harder to prove. In addition, as with all video games, rule of fun trumps all rules of physics.
As many video games attest to, sometimes firing a weapon doesn't have any effect whatsoever on the shooter's momentum, even in the cold, dead vacuum of space where there's NO OUTSIDE FORCE TO CORRECT THE FORCE DUE TO IMPULSE! Impossible, no? Well, in some cases, no, it's not quite impossible.
While many might immediately think of rocket launchers, which are self propelled, and therefore would have minimal effect on the momentum of the shooter, these are not classified as recoil-less weaponry in the traditional sense of the term. Recoil-less weapons, specifically rifles, fire modified artillery shells which still behave as a simple projectile after leaving the weapon. How does this work, then? While a normal rifle would cause the gasses inside the bullet to expand in a closed chamber, propelling the bullet forwards at high speeds out of the barrel, recoil-less rifles allow for some of the gasses to escape out the rear of the rifle, compensating for most of the recoil which would normally result from launching a projectile.
This actually allows for two different side effects. First, this allows for the removal of heavy recoil mechanisms and the reduction of weight of the barrel. Second, it reduces the velocity of the launched projectile. In order to compensate for this, most recoil-less rifles launch a much heavier projectile a shorter range, in order to take advantage of the relatively light weight of the rest of the weapon.
As anyone who's ever heard the story of William Tell can attest, shooting an object with extreme precision, especially something like an apple off of someone's head, with a bow and arrow takes a ton of skill, practice, and luck. It gets even crazier when you see somebody shoot an object the size of a dime flying through the air. Just how do stunt archers do this?
First of all, its nowhere near as easy as "train until you are 100% accurate," as arrows don't fly straight. What's that? Years of high school archery in gym proves otherwise? Well, first of all, congratulations on actually being able to aim, and second of all, you're only examining the arrow's flight path as a whole. Yes, the arrow's center of mass does behave like a simple projectile, so, for larger targets, its fine. However, as the arrow flies, the shaft of the arrow actually bends back and forth in a motion resembling a wave. This motion actually is what enables the arrow as a whole to fly in a straight line, as it otherwise would simply fall flat on the ground. As such, stunt archers need to be able to figure out where the arrowhead will be when the arrow travels to its target. This, believe it or not, can actually be brought down to a science. Simply by knowing the strength of the material that the arrow is made of, as well as the distance between the arrow and the target, archers can accurately predict if the arrowhead will actually be in the right position to hit the target. As such, most stunt archers actually use a device to measure the strength of said arrow, and will only shoot with arrows falling within a very specific range.
In the Borderlands series, specifically Borderlands 2 and Borderlands: The Pre-Sequel, corporate villain Handsome Jack and the company of Hyperion use a device on their moon base/corporate HQ to launch supplies and killer robots down to the planet of Pandora and its moon, Elpis. But just what is said device?
During the beginning of Borderlands: The Pre-Sequel, you get the luxury of being shot out of the moonshot cannon in an emergency evacuation. Fun! But, in the chamber for the moonshot, there is no visible propulsion device: no explosive charge or rocket to launch it. So what does propel the moonshots? Simply put, the moonshot cannon acts as a railgun.
So, how does a railgun work? By connecting a projectile between two long rods, and running a current through the rods, it's possible to create an induced magnetic field which launches said projectile without the need for a conventional propulsion mechanism.
Many have seen the Back to the Future trilogy, in which Marty McFly and Doc Brown use a modified DeLorean to travel through time. According to Doc Brown, the machine requires "1.21 Jigawatts" of power (confirmed by the directors to simply be a mispronunciation of Gigawatts) to power the flux capacitor, which enables time travel. This is achieved by bringing the DeLorean up to a speed of 88 mph, roughly 39.34 m/s. Using this information, I will do what any sane person would do: calculate the mass of the DeLorean.
Before I can calculate the mass, there are a few missing pieces I need to know or assume. First, the coefficient of friction between the tires and the road. Considering that roads at the time were mostly made of concrete, it's safe to use the coefficient of friction for rubber on concrete, which will be somewhere between 0.6 and 0.85. Being the car is in motion, and the wheels are rotating, the static coefficient of friction should be used, so I'll take the higher value of .85. Second, I'm going to assume that air resistance is negligible in this case, and that all work done on the DeLorean comes from the force of friction, which is used to accelerate the car forwards. Finally, I'm going to assume that the DeLorean moves with a constant acceleration, such that the average velocity of the car is equal to half the final velocity, or 19.17 m/s.
With that done, I can work backwards from the beginning to determine the DeLorean's mass. First of all, being power can be calculated using the equation P=F•v, and the net force on the car and velocity of the car are in the same direction, Net Force = P/v = 1.21 x 109 W / 19.17 m/s = 6.31 x 107 N. Being friction is the only force acting to accelerate the car, this is also the force of friction. Now, being the force of friction = µ(Force normal) = µmg, the mass of the DeLorean = Ffriction / (µg) = 6.31 x 107 N / (0.85 x 9.81 m/s) = 7.57 x 106 kg. Looking up the actual value for the mass (yes, you can find it), it's about 1230 kg, a large discrepancy. While the assumptions made above, especially concerning air resistance, don't help the numbers, the fact of the matter is that Doc Brown never fully explained how the DeLorean worked, so it's almost impossible to calculate a realistic number for its mass. Besides, would you really want him to? If so, be prepared to sit through a full movie dedicated simply to explaining the science behind it before even beginning the actual trilogy.
In the previous post, I referenced a quote from Toy Story, said by Woody after Buzz is first introduced, in response to Buzz's stunt around Andy's room. If you haven't seen the first Toy Story (which I don't know why you wouldn't have by now) turn away now before I spoil a minor part of the end of the movie. You know who you are. Alright, here it goes...
At the end of the movie, Woody and Buzz are trying to get back to Andy, and have to chase a moving van on RC. In the process, Buzz lights a firecracker that was attached to his back, sending him and Woody into the air to eventually fly down into Andy's car. Simple, right? Well it is, until you realize that Buzz and Woody, even if you refer to what they did as gliding, shouldn't have been able to stay aloft. Disney's artistic physics license implies that Buzz's "wings" were enough to keep both him and Woody aloft, due to air resistance. While the pressure differential above and below the wings due to moving air would cause that in real life, the shape of Buzz's wings don't allow that. Because Buzz's wings are flat, the amount of air pushing up on the wings will equal the amount of air pushing down on the wings. If you don't believe this, just look at any airplane. The curvature of the wings is what allows air resistance to keep the plane aloft in the first place. In short, Buzz's flight was impossible, and would have been even more difficult while carrying Woody.
Let me start this by saying that the title is a bit of a misnomer. Dogs cannot fly, no matter how fast of a running start they can get. While a hyper dog may be able to leap over several people, an ottoman, and half a couch with a single bound, they have no way to force air down such that they stay aloft. In the words of Tom Hanks, "It's not flying, it's falling with style."
Having said that, dogs actually can do a ton of cool things. Namely, standing on their two rear legs. The canine body is most certainly not designed for them to put their full weight on two legs, yet they are quite clearly capable of such a feat, as many internet videos can testify to. As such, how is this possible? While their center of mass isn't usually directly above their point of contact with the ground, meaning gravity would pull them down, dogs get around this with one simple trick: jumping. Almost every video where dogs are on their hind legs has them jumping on them to stand up. What does this do? Quite simply, with the way that they jump, they cause a torque on their bodies which cancels out the effect of gravity, allowing them to stay up in such an unnatural manner.
In the world of Pokèmon, creatures cute and fearsome are forced to fight one another by their trainers for personal amusement. But its fun, and the little buggers are left relatively unharmed (aside from Gary's Raticate, may he rest in peace), so hey, no harm no foul, right? And considering that this universe was able to spawn said creatures, it must operate on a slightly different set of rules, right? Yet one specific aspect of the universe tends to break a law that, for the most part, is held constant. That aspect is Pokèmon evolution, and the Law of Conservation of Matter.
While animals in real life are known to grow over a long period of time, Pokèmon can go from a small, 10 kg fish to a raging, 235 kg dragon in a matter of seconds, an almost 2300% increase in mass. This has to break the Law of Conservation of Matter, right? Well, as a recent Game Theory video points out, it might not. To sum up the video's theory, which uses the same example, during evolution, the 'mon absorbs matter from the surrounding environment, until it has enough materials to become said giant dragon. However, the video assumes that the 'mon absorbs specific compounds, and as such, shouldn't be possible, due to the low density of certain resources in most areas. However, the video fails to notice one specific alternative:
Einstein's Theory of Mass - Energy Equivalence.
According to Einstein's theory, mass and energy can be related with the equation: E = mc2. Assuming that Pokèmon uses this principle in evolution, they would only need to store enough energy to convert to the required mass, which also explains two things: the flash of light during evolution, and evolution via stone/location. The flash of light could be released during the process as extra energy lost in kick-starting the process, while evolution stones and locations could contain large amounts of energy which specific 'mons have catalysts for, allowing for them to evolve without the need for a long energy gain process. Heck, even trade evolution could be explained, being the 'mon is temporarily converted to energy, and the transfer could supply a large amount of energy which essentially catalyzes the evolution.
Recently, my family and I went to the Strong National Museum of Play, amd I had to try and find a way to keep from being bored while my sisters were in the Bearnstein Bears room. Luckily, there was a huge pinball exhibit just next door, so I did what any sane person would do... and spent half an hour of my life staring at blinking lights and trying not to rage quit every time the ball fell between my flippers. Needless to say, fun times! Having said that though, there's actually alot of physics in pinball that can give you a slight edge.
First of all, how does the ball keep sliding back down to its inevitable doom? The answer: the slope of the table. Because the machine is on an incline, gravity will act on the ball such that it rolls towards the flippers.
Second, how can you read where the ball will go? While I doubt anybody has the time to measure out ball speed, moment of inertia of the flippers, etc., etc., by understanding the basics of momentum, you can get a general idea of the final direction the ball will move in. Because momentum is a vector quantity, by figuring out which way the ball is moving, and hitting the flipper so that where you want the ball to go is between the ball's velocity vector and the flipper's velocity vector, the ball should roughly go in the direction you want.
Black holes: one of the most (theoretically) dangerous things in the universe. They consist of highly concentrated matter at a single point, such that the gravitational force exerted by the black hole is so great, even light cannot escape. However, this isn't entirely because the escape velocity is greater than the speed of light. Some astrophysicists believe that the major reason light cannot escape is because the mass of a black hole is so concentrated that it warps space around it such that every path leads towards the center of the black hole.
In addition, the high gravity of a black hole causes some time dilation. In theory, if we could get close enough to a black hole to experience the effects of time dilation, but not so close that our escape velocity would be too great to leave orbit, we could utilize a blackhole to create forward time travel. The major problem, however, would be getting back afterwards.
So, today I saw a show in which a circus was being performed, and saw one of my favorite types of acts, the tightrope walker. Though it's one of my favorite acts, as a kid, I always wondered why they carried around the big, funny looking stick. Wouldn't having more weight make it harder to walk the rope? Actually, it's quite the contrary. The weight of the pole, extended over the distance, makes it easier to balance. Without the rope, they'd have to wiggle around like crazy on the rope in order to stay on. With the pole, by making slight changes to the angle of the pole, the torque on the pole makes major corrections to the walker's balance. As such, it creates the illusion of elegance atop the rope.
Let it be stated that I am a huge Legend of Zelda fan. I've played a ton of the games, and have even made it a personal goal to seek out a couple of the "older" ones. One of my two favorite games from the franchise is The Legend of Zelda: Majora's Mask, in which the player runs around the land of Termina with a 3 day time limit, trying to prevent the moon from falling and destroying the planet, and using magic to periodically reset time. This game is one of the darkest, yet most emotional in the franchise. However, it doesn't quite handle gravitational physics well.
Considering the moon in the game is constantly approaching the earth, the force of gravity should be constantly increasing, and the acceleration of the moon due to gravity should also be constantly increasing. Despite this, the moon appears to fall at a pretty constant velocity, and even seems to slow down in the game over screen, right before it hits the earth. In addition, in the actual ending, the moon's descent isn't stopped until it gets extremely close to the earth. Assuming I'm wrong and the moon is accelerating towards the earth, considering the moon's mass and the relatively great impact velocity, the force required to change its momentum from its initial momentum to 0 would be so great that there would be some form of crater on the earth's surface from where the four giant's who actually stopped the moon from falling were standing.
One of the most beautiful, awe inspiring landscapes to explore in a video game is none other than the floating island. Imagine being surrounded by plains, forests, mountains... and blue sky and clouds as far as the eye can see. As beautiful as they are though, just how do they stay in the air?
Some games offer a semi-plausible explanation, such as giant fans on the bottom of islands, or simply "It's magic." Other games, however, offer no explanation whatsoever, and the islands simply float. The force of gravity should be pulling them down, and there isn't some giant hand holding it up, so there's no physical force pusing it up against gravity. This leaves two options:
1) A force field, likely caused by magnetism, creates an upward force on the island which counteracts gravity.
2) The island pushes something else (air) down. The impulse of the air over time causes an oppsite force on the island which counteracts gravity.
Both of these are semi plausible, until you actually factor in entering and exiting the island, which changes the island's mass, and would cause it to move due to unbalanced forces. In the end, maybe the "It's magic" definition is better.
Something tells me that the junior/senior class trip to Italy might not be happening this year, as Italy has recently been hit by a series of earthquakes, the most recent of which hit cental Italy and was a 6.6 on the Richter scale. According to recent news, approximately 90% of buildings in the area, many of which had significant historical value, were affected or destroyed by the shockwaves, and many were injured (luckily no reported casualties). As the shockwaves radiated from the epicenter, surrounding areas felt aftershocks of around 4.4 on the scale, and aftershocks are estimated to continue for the next week or two.
Being forces between two tectonic plates at fault lines are what cause these tremors, it can be assumed that there's been an increase in the amount of tectonic activity underneath Italy. For everyone's sake, I hope these tremors end soon, because if they migrate any further south, there may even be a chance we see Mt. Vesuvius erupt again.
I wish the best of luck to the people of Italy in rebuilding and returning to their normal lives. My heart truly goes out to them.
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