If someone asks why physics is so important, tell them that the world just wouldn't work without it. Not the way we know it at least. As this is my final post of the year, I thought it'd be a cool idea to talk about what the world would be like if certain parts of physics didn't exist. In a previous post, I discussed the difficulty that would come with living in a world without friction, and I also mentioned how without electrostatic force, objects would phase right through each other. It would
Pressure is an interesting topic. It's used all around us in things we take for granted. Soda cans are under pressure, airplanes keep air pressure the same so we can breathe when it's really high in the air, hydraulic lifts take advantage of water pressure. It's everywhere. Forces can act on an object due to differences in pressure, going from high to low. Let's use the soda can as an example. When you open a soda can, it fizzes because of the pressure released. If you were to take a the same un
Technically, objects never really make contact with each other. when you put something down on a table, or stand up on the ground there is a very very tiny gap between the object and the table, or your feet and the ground. This happens because the electrons in the atoms of both objects repel each other. This is what keeps us from going right through objects since most of matter is empty space. But if it's an electrostatic force, why do we only feel it upon "contact"? Well, while atoms are compos
As a kid, I liked making extensively large trails of dominoes standing up. Knock one down and the rest would be set in motion. I remember wondering why they tipped over and fell instead of just sliding across the ground when hit. The answer to that is friction. Because of its orientation, when standing up, pushing against it won't just slide it over, but also cause friction to act at the bottom. Because the forces act at a distance from the center of mass, a net torque acts on the object, tippin
People always seem to try and test their balancing skills in almost every way possible, from stacking things on top of each other, to treacherous tightrope walks. But what exactly does it mean when something is balanced? It means that the object is not moving, so the net force, and net torque on the object is zero. The torque on a free standing object that can cause it to fall is the result of gravity acting on its center of mass while it's not centered. Theoretically it is possible to balance a
Conservation of momentum is a very important law. A rather interesting idea popped in my head earlier pertaining to this. Since momentum is conserved, wouldn't it be theoretically possible to lift off of the ground by hitting the ground fast enough with your hand? (Assuming you don't break something or get hurt.) If you're on a slippery surface or on something with wheels you can push off of a wall and slide in the opposite direction, so wouldn't something similar work vertically? Momentum is al
Relative motion can be a bit weird when you really stop to think about it. It may seem to make sense that when we are standing still we don't move, but think about it. Why is it that we don't move when the earth is rotating really fast under us? Friction? Nope, that doesn't answer it. The reason is because while the earth is rotating, whatever point we are on, we move with the same tangential velocity of the earth. So while relative to the ground we may not be moving at all, relative to some obs
I'm sure many of us remember making these out of papers at home, with friends, or in school even though we may have been told not to. You fold the paper into the place, throw it forward, and it glides straight forward. Or sometimes at some weird angle if you didn't do it right. But what keeps them in the air longer than a lot of other things, and what makes them turn weird ways sometimes? Well, in addition to the downward force of gravity, a drag force caused by air acts opposing whatever direct
Waves are everywhere. Sound, light, and even matter. They're what let us see the world around us, and what let us hear things (well, other than our eyes and ears respectively). Waves are what make sounds possible. When I was hanging out with a friend of mine the other day, in the middle of a conversation, he blew into the soda bottle he was holding and it made a noise. Being the physics enthusiast that I am, I decided to explain why that happens. Blowing into the bottle produces sound waves caus
Before you ask, no, we're not talking about the band. We're talking about current. Specifically the current that runs through everyone's houses, and some interesting facts about it. For those who didn't already know, almost every household outlet provides alternating current to whatever is plugged into it, yet a lot of electronic devices, like phone chargers, take direct current. So why is AC used? Well, part of the reason is to make use of important devices called transformers. They're those bu
Suction cups are strange when you think about it. It's just a curved piece if plastic but it can stick to walls. So what makes it so different that it doesnt just fall from the wall? Normally if you try to stick an object to a wall, it just gets pushed away by a normal force. However in the case of a suction cup, when you press it against a surface, the air underneath it is pushed out and creates a vacuum, creating a difference in air pressure. This causes air to apply a force that keeps it agai
Sometimes, science fiction captures some ideas that are both interesting and terrifying, especially when it's something that could be possible. One videogame from the outrageously large Call Of Duty series, Call Of Duty: Ghosts (seriously, they have made way too many of these games) has a weapons satellite orbiting the earth called Odin, that drops metal rods from space that fall to earth's surface and seem to explode on impact. Seems like complete nonsense right? Well, actually it's a concept t
What if we lived in a world without friction? Well, it would probably make everything really difficult. And I mean really difficult. One thing that would be made near impossible to control would be transportation. The very way we walk depends on friction between the ground and our feet or shoes, so if we tried walking, we'd slip, fall over, and slide indefinitely across the ground until we make contact with either a flat surface to push off of, or a round surface, like a street lamp, where you c
It's always a ton of fun. Even when you do find out that it's not a game about strength, but a game of friction because of newton's third law, which says every action has an equal and opposite reaction. so whatever force is applied at one end of the rope by one person must be applied at the other end in the opposite direction by another person. Then it's all a matter of who can apply a force to surpass that of friction. But I had a strange but interesting thought; what if this happened in the va
I'm sure many of us have seen boomerangs in cartoons, or movies, or in real life, and wondered what makes these seemingly magical things come back to the thrower. Well it's actually an interesting combination of things that let them always come back. First is the way it's shaped. Normally a boomerang is two fins, shaped very similarly to plane wings, that are attached at an angle. When thrown, because of their plane wing like shape, air passes more quickly above the fins than underneath, causing
Once thought to be a mere figment of science fiction, these floating skateboards are now all science and no fiction. However, as with almost all technology, it's not without its limitations. A couple of months ago, Lexus created the "slide" hoverboard, a piece of machinery that works because of magnetic force... meaning it only works on magnetic surfaces, an obstacle conquered by the creation of a custom skate park in Spain where most of the surfaces are made to be magnetic. Despite this limitat
Through the years many man made satellites have been placed in space for various purposes. But what keeps them up there without crashing into eachother so debris doesnt fall to the earth? With around 2000 satellites drifting around the planet, something has to stop them from colliding, right? When satellites are launched into orbit, their orbit is recorded, and others are launched with orbits such that no two will collide. However, over very long periods of time orbits can shift slightly, so tec
I'm sure some of us remember these brightly colored blasters that lined our toy boxes as kids, and the backyard shenanigans shared with friends. But what many of us probably didn't realize is that what we held in our hands was a spring loaded product of physics. When pumped back, a spring inside the blaster would be compressed, and held in this state by a small contraption attached to the trigger. When the trigger is pulled afterwards, this contraption moves out of the way, allowing the spring t
Ah, the holidays: a time of cold weather, happy feelings, and peppermint flavored everything! What's not to love? with everyone getting their decorations up right around now i thought i'd talk about a simple thing with some simple physics to it: putting ornaments on a Christmas tree. If you get a real tree every year like me and my family do, then you probably run into the problem of trying to figure out what ornaments to put where because certain ones on certain branches will bend the branches,
Ever been really bored and done something really random? Ever been really really bored and pondered the physics of said random act? I know I have. Just the other day while sitting at a table, I got bored and had a penny in my pocket, so I decided to spin it on the table in an attempt to satisfy my boredom. After about five minutes I made some interesting observations. One thing I noticed is that every time it spun, it would slide across the table. At first I thought this was because the table wa
Superpowers would be awesome. I think that's something we can all agree on right? Like how awesome would it be to fly or be able to teleport places? It sure would save alot of time walking to and from school or work every day. But as great as all that may seem, even if superpowers were possible who's to say they'd be safe? Let's take a look at another superpower that would make traveling places alot faster: super speed, like the Flash. Being able to run faster than a speeding bullet sure would s
After learning about and studying physics for a while, sometimes you just start thinking about how it applies to what you're doing right now. And while it may warrant a few odd looks from friends and family if you're like me and voice those sudden realizations, it can be quite fascinating, as there are some simple things that have some interesting explanations. Like how walking works because of a normal force the earth applies on you as your leg pushes down. As I was taking driving lessons one d
Whenever it comes to science fiction, in addition to all the impossibilities that already exist, the laws of physics tend to be glanced over or tossed aside for the sake of simplicity or other reasons. This time, I'm talking about gravity, specifically in the game Destiny. The game allows you to explore various planets and locations in our solar system throughout your adventure. so being on different planets means gravity has to change, right? well for the sake of in game mechanics this is unfor
In the wonderful world of Star Wars lies yet another example of impossible technology that the laws of physics have no way of explaining: lasers used in both guns and the iconic lightsabers. The lightsaber is basically a beam of light and heat energy on a handle that can slice through pretty much anything with the exception of another lightsaber. as much of a cool idea as this may have appeared in our heads, there is unfortunately a number of reasons why lightsabers won't be real any time soon.
Trampolines are always a ton of fun, but they're one of those everyday things a lot of people don't really question. it's one of those things people just take as common sense, but what makes them work the way they do from a physics perspective? how is it that they can propel a person so high in the air, and why is it that jumping on one somehow sends a person higher than simply jumping on solid ground? the answer is that on a trampoline, there is an extra force acting on you each and every jump.
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