# VagueIncentive

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1. ## Shattering My Phone Screen

Makes sense, hopefully you don't have to experience this whole thing again, because breaking a phone sucks. Good and logical physics though
2. ## Bottle Flipping Physics

The trend of flipping a water bottle through the air to make it land upright again grew rapidly, and has some interesting physics behind it. The difficulty in the trick comes from the fact that when the bottle isn't full, it doesn't spin around the center. What happens is the center of mass goes toward the bottom as more of the liquid is drained, so to the average observer the bottle flips in a strange and unpredictable way. But the rotation of the bottle is predictible, because the axis of rotation is the center of mass of the bottle. If you know this, it makes it easier to predict the movement of the bottle. The easiest center of mass would be close to the bottom, at a point where the height if the liquid equals the diameter of the bottle. This seems to make the motion of the bottle very predictable, as it makes the bottle rotate around the bottom.
3. ## Stage Physics

Almost every stage production uses a pulley system or some sort of rope system to suspend something. Whether it be a curtain, backdrop, or even an actor, using counter weights to hold something up is an old practice. Ropes are all brought down from the ceiling to a row along the wall, over pulleys. These ropes have a plate with vertical pipes on the bottom, and the weights rest on top of the plate. The other end is attached to a horizontal bar on the stage, which multiple things can be attached to. If the weight equals the weight of the bar and what it's carrying, then the pulley system won't move. The weights won't ever be exact, so a brake system to lock the ropes in place is used to ensure that the bar is held in place.
4. ## Physics in Games

Half Life 2 was the first game to have a proper 3d physics system implemented, and while it wasn't flawless, it worked. It allowed the player to grab specific items, and carry them around and throw them into other objects, which would react accordingly. This was shown off a lot throughout the game, since the developers were proud of it. Now, it has become commonplace for almost every game to have a physics engine, as it's called, although it doesn't have to be a main gameplay element. The topic of physics is particularly interesting when you look at the most popular genre, first person shooters. Some games use a projectile to calculate where the bullet will go, while others just use a "hitscan" system. Hitscan is when the path of the bullet is determined as a ray, protruding directly from the player's gun. It could go perfectly straight where its being aimed but most of the time there is a small deviation. This method is simple but effective, as it allows for much faster calculations to be done by a multiplayer server. If the ray hits a player, do damage, if not it will either hit a wall or continue on to nothing. The projectile method actually launches the bullet and does all of the physics calculations for it, such as being affected by gravity and other such variables. This method is used by all of the games in the Battlefield franchise, and is an integral part of the gameplay. Because the fighting happens on such a massive scale, having the bullet travel realistically makes a big difference. Different weapons shoot with different initial velocities, and some have less gravity affecting them. This is used to make some of the weapons fair, such as being able to do more damage but having a much slower velocity makes leading and actually hitting the target much more difficult. The drawbacks of this system are that the server is doing hundreds or thousands of these calculations per second, and with up to 64 players on a server at once, it can be very resource intensive. For people with poor internet, it can result in some strange errors, such as a shot hitting you after you rounded a corner, or being hit by shots that clearly missed. Due to advancements in technology, these calculations have become more efficient, and the fact that we can create a relatively accurate simulation of that many bullets at once is an impressive feat.
5. ## Downforce

Formula 1 cars are well known for being among the fastest cars to be raced competitively, and their inner workings are just amazing. These cars are really wide and low, giving them a low center of gravity. This helps with turning, as the centrifugal force doesn't tip the car as much, since there is less torque. This isn't the thing that helps these cars go so fast, their engines are incredible, and the body is extremely lightweight. It's made of a very complicated composite, part of it being carbon fiber. Since the car is so light, it could easily flip or fly up into the air on the crest of a ridge. Because of this, the concept of using wind resistance to push the car down was developed. Called downforce, it's achieved by using large angled wings that are sloped up towards the back of the car. This way, the air pushes the car down into the ground, so much so that at a certain speed the downforce is greater than the weight of the car. Because of this, it is actually possible for a f1 car to drive upside down, although it would be a very difficult feat. Downforce is useful in many other ways, such as increasing the friction between the track and the tires, allowing for tighter turns. F1 cars are able to hold their speed through corners much better than other cars because they don't lose traction at speed. The general convention in racing is to slow down to get around corners, but it's the exact opposite with f1 cars, since if the car slows down the downforce decreases, making the speed at which you can turn at lower. This dynamic makes f1 driving one of the most difficult racing sports in the world, requiring incredible reaction speed and skill to drive.
6. ## Hotwheels

I spent a lot of my childhood with hotwheels, whether it be putting insane tracks together or just watching the cars fly around the track. Hotwheels are best described as miniature cars that can be sent around tracks at ridiculous speeds to do crazy things. Some of the stunts my cars did were jumping tracks, going through King Kong's mouth, and doing loops around other sections of track. The cars are usually launched by two spinning foam wheels that rotate in opposing directions with a small gap in between for the car. This pushes the car really quickly forward, launching it onto the track. Part of the difficulty with setting up a Hotwheels track was getting the "boosters" in the right spot so that the car would succeed in all the stunts and wouldn't get stuck anywhere. Because the cars are small and light, they can be easily launched really fast and can do crazy things. I haven't kept up to date with the new types of stunts and other new stuff, but all of the stunts my cars did blew my mind, because I always believed that if the cars were scaled up to real life, it would work the same way. But physics has taught me otherwhise, because it would be insanely difficult to send a 4 ton car around a huge loop, let alone creating a structurally sound loop to begin with. Hot wheels cars are much lighter for their size than full size cars are, meaning that the whole situation wouldn't work at all. Hotwheels has made some videos of minor attempts to recreate some stunts, and they have all been fairly successful. The way they accomplished this was by scaling down the stunts, and using heavily modified cars. Without this, the cars would have absolutely not completed the loop, and fallen on their roofs. A lot of car or bike stunts involve jumping, or doing a loop. Hotwheels cars are a good demonstration for young kids how friction and gravity affect motion.
7. ## Demolishing Buildings

Everything that goes up must come back down. This is true for everything affected by gravity, including buildings. Demolishing buildings is actually a business, because of how complicated it can be. Sometimes just a bunch of heavy equipment and a few machines will suffice, but with larger buildings like offices and skyscrapers, keeping,the rubble inside the lot as it collapses is a big deal. The way this is done is usually by using controlled explosions going off in sync. The way these explosives are placed is typically on the very center, on support beams and anything structurally integral. This way, all of the rubble falls inward, not intruding on roads and other buildings. Obviously, if a building collapses onto another one it can't end well, so the scientific destruction of buildings is a significant practice. Having been to watch a building being demolished, I can say that it is very loud, and the ground shakes a lot, so much so that it can be mistaken for an earthquake. After it collapses, the dust cloud it sends up is massive, and rushes out sideways.
8. ## The Physics of Hydroplaning

Most people know about what hydroplaning is, but not how it works and how to prevent it, or how to stay in control if it happens. What happens when you are hydroplaning? The car's tires are lifted off of the road by the water. This happens because of the way water moves as it is pushed by the tires. If the tires can't push enough water out of the way, the pressure builds up and lifts the tire from the road, resulting in a complete of friction and as such control. What should you do if your car starts to hydroplane? Nothing. Don't turn, brake, or accelerate, as that can just cause the car to spin out. You should just maintain speed and direction until the water stops. It sounds counter intuitive, but its the best solution to the problem.

Our second lab was an interesting one: predict where the ball will land after one shot from a projectile launcher, and you get a 100. If you miss, its a 0. But, the whole class was involved, so the end result was a very disorganized lab. On the first shot, we measured the angle and change in Y, then the X distance and the time it took from launch to landing. This was used to calculate the resultant initial velocity of the ball. Then the angle and height of ball was changed, so we re-measured them. Using the velocity from the previous launch, the initial velocity in the Y direction could be calculated, and then the time the ball would take to hit the floor. This time, multiplied by the initial X velocity, gives the distance the target should be placed from the ball in order for it to hit. My calculations gave me an X distance of 1.99m, but since it wasn't calculated in time, I don't know what the actual distance the ball covered was. So, I hope my answer is correct, but there is no way of knowing.

AP Physics C. It's hard to believe I'm taking a college level physics class for the second time, but here I am. I have always been interested in the topics that physics covers, because I love pretty much any type of deep scientific research. I've always been good at science, and with technology of most kinds. The relationship between technology and physics is often overlooked, but it plays a massive part in almost everything we take for granted today, like GPS and cell service. How else would we have gotten large hunks of metal to stay up in the sky for years on end? These kinds of things are why I'm taking physics, because I just love it. I'm a very curious person so I thoroughly enjoy learning how the world works, and being able to understand why certain things happen. I hope to learn even more about that kind of thing this year, because I learned a lot last year. That is why I was excited for this class, having the ability to gain a much deeper understanding of the world from a high school class is awesome, and I can't wait to see what this class will unfold. Although it isn't all sunshine and rainbows, with great power comes great responsibility, and in this case that responsibility is classwork, homework, tests, the usual. Except this isn't the usual class, so expecting a usual workload would be ridiculous. The horror stories of all-nighters from the survivors make me nervous, but I will do my best to avoid falling behind, and to work diligently to maintain a good grade. I can't wait to see what I'll learn, but I most definitely can wait on all that work.