Honestly, this whole E & M section of Physics C has not been going so great for me. We're supposed to have our last unit test on electromagnetism tomorrow, but I took it today because I won't be here tomorrow. We finish it the Monday after break, and it's safe to say I left about 75% of that test blank because I didn't know the answers.
I think I struggle with concepts more than anything. I just can't visualize the problem like I could in mechanics, so none of the processes we go through
Since I just rode up one, and because I can't think of anything else to write about at the moment, I guess Ill do the generic elevator blog post.
So, elevators. One of the first things we did in Physics B when learning about free body diagrams, was practice elevator problems. First, in all out FBD's, we would have to draw our weight=mg pointing down because the force of gravity acts downward. Then the normal force, or the force of the elevator pushing up on your feet, would point upward.
See what I did with the title there? I'm so clever.
So, echos. An echo happens when you say something or make a noise and the sound waves from your mouth bounce off a hard surface and rebound back to you, which is why you hear what you said again and again and again. This is why echoes are common in caves, because you're surrounded by hard surfaces.
We know that when a wave reaches the end of its medium, it undergoes a certain process depending on how it's medium ends. Transmission/refrac
And on we go, talking about more physics in Newton's Cradle.
We already talked about conservation of energy, so now let's talk about conservation of momentum. Momentum is a vector quantity, meaning the direction it's in matters. When the first ball is dropped into the second ball, the second ball must keep moving in the same direction, and the first ball doesn't just bounce off the 2nd in the opposite direction; this would be a change in momentum, which cannot happen without the application o
We've all seen it - that contraption with 5 metal balls hanging side by side on strings? You lift one to the side as if it were a pendulum, let it go, and it swings into the others - causing the ball on the very opposite side to go up. This is called Newton's Cradle, named after the big guy himself.
There are a number of physics laws at work here. First, the law of conservation of energy: as potential energy is maximized and kinetic energy is zero when the end balls swing to their highest poi
Recently I sat at the table eating dinner, when I noticed a flutter in my peripheral vision, drawing my attention. I turned my head to see my cat batting at a cat toy someone had hung from the table...one of those sticks with the string attached and a feather or fluffy thing at the end, ya know? You wave it around like a wand and your cat pounces after it?
Anyway, someone in my family had set it up so just the string and attached feather hung down over the table, just within my cat's reach.
Recently (on a much cooler day), I discovered something while driving to volleyball practice at night. It was chilly so I had the heat on in my car, but just on low. Upon turning on the highway, I suddenly noticed that the heat seemed to have been turned up! That wasn't right, how could it do that on its own?! I double checked it, but the switch hadn't moved; the heat was still on the lowest setting.
So why did it feel like hot air was blowing twice as fast into my face? Well, when I thought
It was first Aristotle who discovered what is now known as the Mpemba effect: that hot water actually freezes faster than cold water. Scientists have struggled to explain this for years, until recently.
We all know that "water" is made up of two hydrogen atoms and an oxygen atom, more accurately known as H20. Cold water is made up of short hydrogen bonds and long O-H covalent bonds, while the opposite is true for warm water. It is these hydrogen bonds that act weirdly and have drawn the atten
Warning: this blog post may get a little gross if you don't like mucus-related physics talk. Reader discretion advised.
So, ever wonder just how fast you sneeze? Or rather, how fast the snot comes out of your nose when you sneeze?
Well, so did Adam and Jamie on Mythbusters. They investigated a myth that when sneezing, the mucus can eject from your nose at speeds of up to 100mph. That myth was busted though, and they instead found snot-rocket speeds to be only about 35-40mph. Still - that
The Physics-C midterm approaches.
While frantically searching the depths of my mind (and the internet) for an idea for my last blog post, I looked up to realize the time and scolded myself for not finishing these blog posts earlier. Why do I always wait until last minute? This is time I could have used to study.
So in a feeble attempt to finish in time to cram in some legit studying (because I don't think blog-post writing counts as studying) for both Econ and Physics tomorrow, I decided
Cow tipping - is it really possible? We've all heard about that awesome prank the teenagers of our parents' and grandparents' generations used to pull...but can it really be done?
First off, I'd like to assert that in no way do I condone cow-tipping or the bullying of any other farm animals. Because hey, cows are people too.
Anyway, onto the physics. First off, cows don't even sleep standing up, contrary to popular belief. So, assuming they stay in place and don't run away when you try to
I recently stumbled upon a question that definitely made me think twice. And then twice more.
If you carry firewood to the top of a hill, and then burn it there, what happens to the firewood's gravitational potential energy? Does it disappear?
Crazy, I know. The equation for gravitational potential energy is mgh, or the mass times the acceleration due to gravity times the height. If you burn the log up into ashes with substantially less mass, what happens to the rest of the gravitational
Did you know that, when you wear high heels, you can literally dent the floor? (A wooden floor, of course.)
So not only do these things torture your feet, but they also do damage the floor you walk on? Still worth it?
Let's say you're a girl, drag queen, or just a regular guy who enjoys wearing high heels from time to time, and you weigh about 130 pounds. Let's also assume your shoes - regular flats, that is - have a bottom surface area of about 10 square inches. With heels, the bottom s
We've all heard the myth. Drop a penny from the top of the Empire State Building, it will gain enough velocity to do considerable damage to someone standing on the sidewalk - plunge a hole through their hand, or, in more gruesome versions, their head.
Though at first this thought seems plausible (considering the height of the Empire State Building and the acceleration due to gravity), it's important to realize that - due to other important factors - this myth is busted.
When we first releas
Static electricity is a stationary electric charge that is built up on a material. We might experience static electricity when touching a doorknob or rubbing our feet on the carpet and shocking a friend - sometimes we can even see a spark. This static electricity is formed when we accumulate extra electrons and they are discharged onto another object.
So we know that electrons are tiny negatively charged particles, and protons are tiny (though not nearly as tiny as electrons) positively char
It is often believed that, when turning in a car, you lean the opposite way of the turn. Turn right, you feel a force left. This is a common misconception.
In actuality, as the car turns right, our bodies' inertia (directly proportional to mass) keeps us wanting to travel in a straight line, which is why we feel thrust leftward. This is also why, when we slam on the breaks, our bodies jerk forward - they want to keep going straight.
The above explanation makes sense, but I've always wond
Parkour, sometimes referred to as "free-running", has always fascinated me. How do they do it? I for one can't even do the simplest of parkour stunts, but I looked into the physics of it a bit, and thought I'd share what I found.
Of course, these stunts seem scary to us because, frankly, they hurt when we try to do them. Or when I try to do them, anyway. In order to make it hurt less and avoid broken bones - to lessen the impact upon landing after a fall, or to decrease the force upon a set
So you know those toys where there was a wooden ball attached to a string attached to a wooden handle thing? And you had to swing the ball up and catch it in a ball-shaped indentation on the top of the wooden handle thing? No? Well, maybe a picture will help...
Anyways, it took me awhile to find this picture, as apparently Google has no idea what you're talking about when you search "swing ball on string into indentation" or similar phrases. Finally, I found it's real name - "Cup and ball"...
Since we're learning about rotational kinetmatics and such in class, I thought it would be a good idea to stick to circular motion.
So, carousels. Since we know that velocity equals distance over time, obviously the longer the distance the longer it would take to reach the destination. Carousel horses, though they may look like they're all moving at the same velocity, actually have different linear velocities depending on how far they are from the center of the carousel.
The more you thin
Yay for more circular motion! So does anyone know what I'm talking about when I say "playground spinny things"? There like mini merry go rounds for playgrounds, but like...without the animals and cheesy music. Someone goes on them and you spin them really fast? There are funny fail videos on the internet of people spinning super fast on them and then flying off? Sound familiar?
I hope so, because I really don't know what they're called. But anyway, I thought I'd talk about the physics behind
So I figured it was time I do a sports post, since it seems to be a super popular blog topic recently and I can't think of anything else to do at the moment. Time for the physics of volleyball!
Jumping right into it (haha volleyball puns ), I'll start off with the serving part. So when you serve the ball over the net, it becomes a projectile whose distance is dictated by the force at which you hit it. Assuming there is no initial vertical velocity and you hit the ball straight over the net,
We've all experienced it. You're walking in the hallway, the not-so-trafically-ideal hallway (we really need to invest in a double yellow line down the middle so everyone walks the right way...), and suddenly you and a stranger come face to face. You awkwardly try to maneuver around eachother, both stepping the same way...twice. I find myself in these situations daily, so I thought it'd be cool to think about the physics behind it.
As you walk forward, you have a forward momentum of mv; m be
So these past two weeks we've been doing an independent unit on momentum, and I just thought I'd share my thoughts on it.
On some level, I like the independence of this unit: going at my own pace, picking what I want to do each day, doing stuff in whatever order I want, working with other people, etc. It's nice not to have a structured class period every day, and I like learning at my own pace.
But then again, there are definitely aspects of this unit I'm not fond of. For example, I really
So I figured I'd write a blog about my experience in building my first ever catapult! Though it was definitely intimidating at first, I found the project actually turned out to be a lot of fun to build and launch.
My group settled on a trebuchet design, and after working out the ideal angles, sizes and overall plan, we got to building. We built for 2 days, just about 3-4 hours a day. I won't bore you with the cutting and sizing and drilling of wood, because I think we all know that's not exac
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