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Name: Mechanical Energy of a Satellite in Circular Orbit Category: Circular Motion & Gravity Date Added: 2018-03-04 Submitter: Flipping Physics The mechanical energy of a satellite in circular orbit is solved for in terms of universal gravitational potential energy. And the velocity of the satellite is compared to escape velocity. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:14 Types of mechanical energy of a satellite 1:21 Solving for the velocity of a satellite in circular orbit 2:34 Solving for the mechanical energy of a satellite 3:31 Comparing satellite velocity to escape velocity Next Video: Impulse for Two Objects being Attracted to One Another Multilingual? Please help translate Flipping Physics videos! Previous Video: Deriving Escape Velocity of Planet Earth Please support me on Patreon! Thank you to Jonathan Everett, Christopher Becke, Sawdog, and Scott Carter for being my Quality Control Team for this video. Thank you to Youssef Nasr for transcribing the English subtitles of this video. Mechanical Energy of a Satellite in Circular Orbit

In the following diagram, a force F acts on a cart in motion on a frictionless surface. The initial and final velocities of each cart are shown. Rank the energy required to change each cart's velocity from greatest to least. A: Weighs 2 kg, 5 m/s to 2 m/s - Change in KE = 1/2*2*(2*2-5*5) J = -21 J B: Weighs 3 kg, 3 m/s to -3 m/s - Change in KE = 1/2*3*(3*3-(-3)*(-3)) J = 0 J C: Weighs 5 kg, 5 m/s to 6 m/s - Change in KE = 1/2*5*(6*6-5*5) J = 27.5 J D: Weighs 4 kg, -1 m/s to 2 m/s - Change in KE = 1/2*4*(2*2-(-1)*(-1)) J = 6 J The answer says that the ranking is C, B, A, D, which doesn't make any sense to me given the calculations I made. Can someone please explain what I did wrong, or clarify the question?

Name: Review of Mechanical Energy and Momentum Equations and When To Use Them! Category: Momentum and Collisions Date Added: 2017-02-16 Submitter: Flipping Physics By the time students learn about all the equations for mechanical energy, momentum, impulse and impact force, they often start to confuse the equations with one another. This is a straightforward, simple look at all of those equations and when to use them. This is an AP Physics 1 Topic. Want Lecture Notes? Content Times: 0:14 Tacky Sweater Day! 0:22 Conservation of Mechanical Energy 0:54 Work due to Friction equals Change in Mechanical Energy 1:30 Net Work equals change in Kinetic Energy 3:01 Conservation of Momentum does NOT require the work due to friction to be zero 3:28 The initial and final points when dealing with momentum are predetermined 3:56 Impulse does not equal Impact Force Thank you to Sophie Jones and her family for letting me use six of their sweaters in this video! Next Video: 2D Conservation of Momentum Example using Air Hockey Discs Multilingual? Please help translate Flipping Physics videos! Previous Video: Impulse Comparison of Three Different Demonstrations Please support me on Patreon! Thank you to my Quality Control help: Christopher Becke, Scott Carter and Jennifer Larsen Review of Mechanical Energy and Momentum Equations and When To Use Them!

Something that baffles scientists today is a strange situation called the Fermi Paradox, named after Italian physicist Enrico Fermi. The basic conundrum is that there's an incredibly high probability that alien life forms not only exist in the universe, but nearby Earth. The reason for this statement is the radically large number of solar systems in our galaxy alone. With so many stars in the observable universe, billions are similar to our Sun. The likelihood that many of these stars have Earth-like planets is therefore quite high. Assuming Earth is a typical planet, intelligent life must have developed on many of these planets. Our planet has existed for about 4.5 billion years in a 14 billion year old universe, so there should have been plenty of time for countless organic lifeforms to develop space travel and begin exploring our galaxy, since humans have come thus far in only 200,000 years. Finally, with rough estimates based on current hypothesis for interstellar travel (which may in fact be very slow and inefficient) the Milky Way Galaxy could be traversed in only about a million years, and totally colonized in about two million. So, scientists wonder, where are all the aliens? Why, if life in our galaxy has had so many chances to exist, do we have such little evidence of extraterrestrials? Well, there are several different hypotheses. One idea concerns filters. This idea states that life has many difficult to pass barriers which make its existence incredibly difficult. We've passed some already, such as the still undiscovered process through which life originates, mutually assured destruction, and extinction events. Perhaps the universe was actually incredibly hostile and dangerous for any life until only recently, making humans some of the first ever. And, there are great filters in our future as well, such as irreversible climate change. Maybe there's some impassible filter we don't know of, and won't for a long time, that no life form has yet to defeat. Plenty of people have already assumed that nuclear bombs and the Large Hadron Collider would destroy the Earth, maybe someday they'll be right. There's also the idea that other life forms are preventing this interaction. Maybe some incredibly advanced life form from far away has advanced enough that they can control the entire galaxy, and they don't want other life forms to advance to the point where they pose a threat. Maybe they physically prevent interaction in order to stop the spread of ideas, and prevent any further development. Or, perhaps they act as a filter themselves, and annihilate and race that begins to get too far. Or, maybe we're actually just alone. We could be the first life ever to exist, the only, and the last once we eventually kick the bucket. Any way it works out, scientists still don't really have an answer to the Fermi Paradox, and with good reason. This question is a very confusing, scary, and difficult one to answer. So, for now, all we know is that either there's no evidence of life on Earth, or the government took it.

Name: Work due to Friction equals Change in Mechanical Energy Problem by Billy Category: Work, Energy, Power Date Added: 2016-02-17 Submitter: Flipping Physics Enjoy learning from Billy as he solves a problem using Work due to Friction equals Change in Mechanical Energy. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:21 The problem 0:51 Work due to Friction equals Change in Mechanical Energy 1:31 Determining the Mechanical Energies 2:44 Solving for the Force Normal 3:52 Relating height final to displacement along the incline 5:03 Substituting in numbers Next Video: Deriving the Work-Energy Theorem using Calculus See this problem solved using Conservation of Energy and Newton’s Second Law. Multilingual? Please help translate Flipping Physics videos! Previous Video: Introductory Work due to Friction equals Change in Mechanical Energy Problem 1¢/minute Work due to Friction equals Change in Mechanical Energy Problem by Billy

Name: Introductory Work due to Friction equals Change in Mechanical Energy Problem Category: Work, Energy, Power Date Added: 2016-02-12 Submitter: Flipping Physics The equation Work due to Friction equals Change in Mechanical Energy can often be confusing for students. This video is a step-by-step introduction in how to use the formula to solve a problem. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:09 The problem 1:29 Why we can use this equation in this problem 1:52 Expanding the equation 2:29 Identifying Initial and Final Points and the Horizontal Zero Line 3:00 Substituting into the left hand side of the equation 4:05 Deciding which Mechanical Energies are present 4:59 Where did all that Kinetic Energy go? 5:27 Identifying which variables we know and do not know 5:58 Solving for the Force Normal 6:57 Substituting Force Normal back into the original equation 8:09 Why isn’t our answer negative? Next Video: Work due to Friction equals Change in Mechanical Energy Problem by Billy Multilingual? Please help translate Flipping Physics videos! Previous Video: Introduction to Mechanical Energy with Friction 1¢/minute Introductory Work due to Friction equals Change in Mechanical Energy Problem

Name: Introduction to Mechanical Energy with Friction Category: Work, Energy, Power Date Added: 2016-02-08 Submitter: Flipping Physics Learn how to use Mechanical Energy when the Work done by Friction does not equal zero. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:09 When is Conservation of Mechanical energy true? 0:37 Work due to Friction equals the Change in Mechanical Energy 1:57 Determining the angle in the work equation 3:01 When the angle is not 180 degrees 3:50 What if the work done by friction is zero? 4:31 Always identify … Next Video: Introductory Work due to Friction equals Change in Mechanical Energy Problem Multilingual? Please help translate Flipping Physics videos! Previous Video: The Energy Song by Bo 1¢/minute Introduction to Mechanical Energy with Friction

We all know Einstein's famous equations E=mc^2. It means that energy and mass are two halves of the same variable, and that a little mass makes an enormous amount of energy. We also know its disastrous effects, as evidenced in the US's infamous Manhattan Project. The first nuclear bomb ever tested was dubbed "The Gadget, " and the test itself was nicknamed the Trinity Test. It was conducted on the morning of July 16, 1945 in the Alamogordo bombing range of New Mexico. The bomb was said to release the energy of about 20 kilotons of TNT, or about 84 terrajoules. Now, if we plug that number into Einstein's equation, we can find exactly how much radioactive plutonium was put towards the actual explosion. Using 3E8 as c and 84E12 as E, we find that the mass of the plutonium reacting was about 9E-4Kg. However, I assure you much more plutonium was used to create the Gadget than that. So where did all the rest go? Well, into the massive amount of heat and light created, more than enough to blind people and incinerate standing structures for miles. This conversion seems to be the most powerful force we can today harness, and it truly has awe inspiriing results.

Name: The Energy Song by Bo Category: Work, Energy, Power Date Added: 2016-01-29 Submitter: Flipping Physics Sing and learn about Work and Mechanical Energy with Bo! Want Lyrics? This is an AP Physics 1 topic. Multilingual? Please help translate Flipping Physics videos! Next Video: Introduction to Mechanical Energy with Friction Previous Video: Conservation of Energy Problem with Friction, an Incline and a Spring by Billy Hear "The Energy Song" on Soundcloud. 1¢/minute The Energy Song by Bo

Name: Conservation of Energy Problem with Friction, an Incline and a Spring by Billy Category: Work, Energy, Power Date Added: 2016-01-14 Submitter: Flipping Physics Billy helps you review Conservation of Mechanical Energy, springs, inclines, and uniformly accelerated motion all in one example problem. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:10 The problem 0:38 Listing the known values 1:40 Using Conservation of Mechanical Energy 2:56 Canceling out the Mechanical Energies which are not there 4:18 Drawing the Free Body Diagram 4:52 Summing the forces in the perpendicular direction 5:26 Summing the forces in the parallel direction 6:59 Using Uniformly Accelerated Motion 7:56 Finding the maximum height Next Video: Work due to the Force of Gravity on an Incline by Billy Multilingual? Please help translate Flipping Physics videos! Previous Video: Introductory Conservation of Mechanical Energy Problem using a Trebuchet 1¢/minute Conservation of Energy Problem with Friction, an Incline and a Spring by Billy

Name: Introduction to Conservation of Mechanical Energy with Demonstrations Category: Work, Energy, Power Date Added: 2015-12-18 Submitter: Flipping Physics Ian Terry, winner of Big Brother 14, makes a special appearance to help us learn about Conservation of Mechanical Energy. See several demonstrations and understand when mechanical energy is conserved. Want Lecture Notes? This is an AP Physics 1 topic. Content Times: 0:01 Reviewing the three different types of mechanical energy 0:23 Mr. Terry drops an object for our first demonstration 0:58 Calculating Kinetic Energy and Gravitational Potential Energy 2:53 Mechanical energy data table 3:37 Conservation of mechanical energy graph 5:10 When is mechanical energy conserved? 7:13 A second demonstration of conservation of mechanical energy Next Video: Introduction to Conservation of Mechanical Energy with Demonstrations Multilingual? Please help translate Flipping Physics videos! Previous Video: Introduction to Elastic Potential Energy with Examples 1¢/minute Introduction to Conservation of Mechanical Energy with Demonstrations

Remember those cartoon kids shows where lightning bolts sent you flying into the sky with your pants on fire? I’m talking about a Team Rocket blasting off again sort of scenario. I always thought those were pretty funny, but how would they work in real life? Let’s assume that by the Laws of Disney magic, being struck with lightning instantly converts all of its energy into kinetic energy for the object hit. So, a 50 kg cartoon character gets pegged. The average lightning bolt has about 5 GJ of electrical energy in it, and contact lasts only about 30 µs. The character starts at rest. Kinetic Energy = .5mv^2, so we can calculate the new speed of the character to be 14,142.14 m/s. Let’s say this is actually James from Team Rocket, so of course he shoots up into the air at an angle of about 75° with the ground. Using the kinematics equations this time we can find that his maximum height is about 9,510,832.84 m. I guess they were right all along: James would disappear almost instantly, like a flash in the sky. Huh.

Everybody loves a good hero. But, are they realistic? Some of our favorite crusaders - Batman, Link, Green Arrow - use grappling hooks to get around. I wonder if they’d work like in the games and movies. Let’s say Batman is trying to get into Arkham Asylum to teach some no good-nicks what he thinks of this whole “rehabilitation” thing. He needs to get two floors up, which is about 6.6 m. And, like in the movies, he needs to rocket up that distance, let’s say at about 6 m/s. The average man weighs 70 kg, but Batman is pretty buff, so we’ll make it 75 kg. We can calculate the work needed to be (.5)mv^2 + mgh, which here equals 6205.95 J. We also know v = d/t, so that means t = d/v = 1.1 s. And, power = W/t = 5641.77 W. It’s pretty safe to say a handheld motor like the ones we see in the media couldn’t make over 5.5 kW of pull. A mounted artillery grappling gun could, and are used by the US special forces for stealth missions. However, until our technology evolves a bit more, Batman will just have to learn to actually fly.

Name: Work, Energy and Power Review for AP Physics 1 Category: Exam Prep Date Added: 13 March 2015 - 08:25 AM Submitter: Flipping Physics Short Description: None Provided Review of the topics of Work, Energy, Power and Hooke’s Law covered in the AP Physics 1 curriculum. Content Times: 0:18 Work 1:38 Kinetic Energy 2:13 Elastic Potential Energy 3:02 Gravitational Potential Energy 4:02 Work and Energy are in Joules 4:58 Conservation of Mechanical Energy 5:54 Work due to Friction equals the Change in Mechanical Energy 6:46 Power 7:46 Hooke’s Law Multilingual? View Video

I used to own a half-pipe. Well, a mini-pipe rather. It was a about 1.5 meters tall. Skate baording on it is interesting because at the top of the pipe all you're energy is due to gravity. That means Etop=mgh As one rides down the half-pipe, potential energy is converted to kinetic. At the bottom Ebot=(1/2)mv^2 HOWEVER... In many sports that include a standing on board, a common method to gain speed is to PUMP. Pumping, in its simplest form, is pushing down on the board when you're going up or down a ramp. Or any curve for that matter. Its possible to PUMP on any curve who's concavity faces upwards. In the case of a half-pipe: one can pump on there way down the pipe, thus converting energy in their legs to kinetic energy using an impulse (push). And it works too. Its actually quite crucial while skating on a mini pipe. -Shabba

The higher you are from the ground the more potentional energy you have, the faster you're falling the more kinetic energy you have, but add it up and youll always have the same amount of internal energy. This is pretty much a basic concept of gymnastics. When practicing, the higher the beam is the more potential energy you have, but this also means the harder the fall or the better the dismount when transfered to kinetic energy. Or you could have the beam lower and have less potential energy, the less the fall will hurt but the more difficult the dismount. Youll hope that if the beam is low youll have more power because you have less time to do what you need to do before your feet (or other body part not of choice) hits the ground.

Hello! I'm using the "AP Physics Essentials: 1" book to study for my Work, Power, and Energy exam (chapter 5.) I need clarification on question 5.10; how do we decide on the equation to use? I'm so lost on how to make that determination. Thanks!

In our body, we often consciously use our skeletal muscles. Our nervous system sends an electrical signal to our muscles which affects proteins which cause our muscle to contract. Electrical energy is transmitted which begins a process of chemical energy being converted to mechanical energy. Some smooth muscles behave like skeletal muscles, while others have contractions which are regularly and methodically induced by specific cells. The actions of these cells keep systems such as the digestive system working continuously without conscious thought. The heart, the cardiac muscle, is controlled the same way as the smooth muscle. The cardiac muscle pumps blood through the body, using mechanical energy to bring oxygen to cells where it can facilitate more chemical reactions.

Yooooooo check this out. I was chillin in my studio and i had to open a window (for circulation). As i opened it, a gust of wind hit me in the facial region. But i thought nothing of it. No one ever does. Ever. WIND is overlooked all the time even-though it occurs pretty much all the time. WIND, in its smallest components is simply a MASSIVE amount of mostly oxygen and nitrogen molecules flying around due to diffrences in atmospheric pressure. So, by feeling a gentile wind on your skin, your actually experiencing millions of oxygen atoms smashing into you. But say there's other things in the air around you. Like dirt, or smaller particles like dust, and Smoke. Those particles also smash against you. Ow Now lets talk about pressure. If you've taken chemestry or physics you know that: (p1v1)/t1 = (p2v2)/t2 where p=pressure, v=volume, and t=temperature. This equation represents the fact that within a closed system, pressure and volume have an indirect relationship (as one goes up, the other goes down). Along with this, pressure and temperature have a direct relationship. This being said, if the atmospheric pressure in a certain region increases, the massive amount of atoms making up the air around you will be pushed away from said region... CREATING WIND. whoa. With love, you're friend -Shabba

Everyone likes trampolines. But how do they even work? It's all about energy, and at the same time, proves Newton's laws of motion. Potential energy (PE) and kinetic energy (KE) are the reason trampolines allow you to jump higher than you can on flat ground. One type of potential energy that is involved with trampolines is the potential energy stored in springs. Another type of energy is gravitational potential energy. There is also kinetic energy because you are moving. The equation that connects potential and kinetic energy to find total energy (E) is: E=PE+KE+Q The total energy of the person jumping on a trampoline equals all of the potential energy (both the spring and gravitational potential), plus the kinetic energy. Q is internal energy, which isn't really important here. Other equations needed to understand the forces and energy of trampolines are: PE=mgh This used to find the potential energy due to gravity. You multiply the mass of the object (or person in this case), by the height they are from the ground, by g, acceleration due to gravity. Which is always 9.81 m/s^2. People with larger masses have a greater potential energy due to gravity if they are at the same height as someone with a smaller mass. However, it is harder for people with larger masses to reach the same heights as people with small masses, because gravity is pulling them down more. PE=(1/2)kx^2 The potential energy stored in a spring: "x" is how much the spring stretches, and "k" is the spring constant. Hooke's law goes along with this: F=kx. The force of the spring is the constant multiplied by the change in the spring length. This demonstrates Newton's third law; every action has an equal and opposite reaction. When the springs are stretched by the person, they have to compress again, making the person jump higher as the trampoline returns to its original position. Because of gravity, larger masses allow the spring to be stretched out more. This can be shown by the equation F=ma, which is Newton's second law of motion. "F" is the force of gravity, "m" is mass, and "a" here is also g, acceleration due to gravity. So when mass increases, so does the force of gravity. This means the object/person is being pulled down harder by gravity. This stretches the springs of the trampoline more, creating a higher spring potential energy. But the mass is usually too heavy for the spring to move you if you just stand there, which is why you don't move unless you start jumping first. Smaller kids usually jump higher than adults, even though they have a lower potential energy due to gravity, because the trampoline can more easily spring them back up, since they are being pulled down by gravity slightly less. This is all a great example of Newton's first law: objects in motion will keep moving, and objects at rest will not move, until acted upon by an outside force. The outside forces that keep you on the trampoline are both gravity, which keeps you down, and the trampoline itself, which keeps you up. You also wont move until you begin jumping. Pushing your feet down makes you go up. (Newton's third law!)

So senior year has finally come to an end and we all are saying goodbye. So I thought I would discuss the physics of senior year. The year has had so much physics enwrapped in it, in and outside the classroom. We got to use physics in physics c (duh), calculus, and technology for those who take these classes. With a basic understanding of physics, these classes became easier to learn and master. Outside the classroom, physics was used by every athlete in the school in some shape or form from lacrosse involving torque, to hockey with rotational motion. But there is so much more. Physics was used every time the students went up and down the stairs, or when we used the computers or cell phones (which of course none of us would ever do). There's when we go to the nurses office and they use the thermometer, or when we do our locker combinations to get our stuff. Physics can even be applied to our work effort. the more energy that we used throughout the year, the less potential energy we had to use. Hence, the moment APs were over, almost the entire class stopped working, using at times only the most minimal of effort. Finally, there was the excitement factor. Like with electromagnetism, the closer we got to the end of the year, the more energetic we got, buzzing with excitement for graduation. On that note, I would like to say good luck to everyone in their future, whether that be in college or high school or whatever it is you do, and to continue with physics and stay nerdy!!!

My friends and I go to Zumba classes three times a week and it is very fun. Like any regular physics student, I am constantly thinking about Mr. Fullerton's lessons during class. As we dance, jump, and move I get to thinking... it must take a lot of energy to move around the way we do. But as we eat healthily and exercise more often, Zumba gets easier and easier... why? Here are some of the equations I will be using to help explain this Zumba Paradox... - KE = (1/2)(mass)(velocity2) - PE = (mass)(g)(height) - Work = Change in Mechanical Energy - Work = Force * Displacement It takes work to move our body in all different sorts of ways. Because work is equal to the change in Mechanical Energy, and both Kinetic Energy and Potential Energy are proportional to the mass of the object, it is reasonable to say that work is also proportional to the mass of the object. In this case, the object is our body. As any athletic trainer will happily tell you, a good workout is one where you do the most work. In our case, we will hold everything else constant besides our mass because we are doing the exact same class every time we work out. Put extremely simply, work is how much you move times how much weight you are moving. So, it is correct to say that as you lose mass you will do less and less work each successive time you go to Zumba class. I want to lose weight at a constant rate, as would most females in Zumba class. Constant weight loss is much better than fluctuating weight loss. So how can I keep my weight loss constant, and overcome this work-mass relationship that we discussed earlier? Zumba deals with changes in Kinetic Energy more than other types of fitness training such as weight lifting which deals more with changes in Potential Energy. So for simplicity we will set Work equal to the change in only KE. Here's what we want to happen: C = (1/2)(mass)(velocity2) // With C being a constant positive number that represents an amount of Joules In order for us to keep a constant C, velocity2 has to increase at a rate equal to the rate at which mass decreases. Here's our relationship in equation form: velocity2 = 1/mass // or in exponential form --> velocity = mass-1/2 So there it is, ladies and gents, if you want to lose weight at a constant rate, you need to increase your intensity a little bit each class as you shed the pounds.

The drinking bird novelty item has been around for decades, but it's seemingly simple design is deceptive. Carefully calculated physics principles have gone into the creation of this toy. Mostly, it utilizes energy conversion, operating as a heat engine that changes heat energy from water into mechanical work. The drinking bird design is made up of several important components: -two glass bulbs of equal size attached on either end of a glass tube -a fuzzy, absorbent material to cover the bird's head -two plastic legs connected to the body with a pivot -a small amount of methylene chloide (industrial paint stripper and solvent) liquid in the bottom glass bulb -either a red or a blue hat, depending on the model For the toy to work, the felt tip on the bird's beak must be dipped into a cup of water, which then allows it to absorb a small amount of that water. As the water in its beak evaporates, the temperature in it goes down, which causes the methylene chloride vapor to condense. When this happens, liquid from the bottom bulb is forced upward, toward the head and beak portion. Then, as liquid enters the head, the bird becomes top-heavy and slowly begins to tip forward once again. As the drinking bird does tip, the rest of the liquid goes to the bird's head and the bottom portion of the tube isn't submerged any more. Vapor then travels back up the tube which will then cause the head to drain of liquid again. As the bottom glass bulb is filled with liquid again, the bird becomes more bottom heavy and the entire process begins again.

Throw away everything you have ever learned about classical physics. Forget about everything logic has taught you, and remove any ordinary rules of thought that every sane person uses to make deductions. For some people this may be harder than others, but for me, it's fun. Not like hydrogen bonding is "FON" but like real fun. Mr. Fullerton said, "If you understand Quantum Physics, you must be an idiot, or should have a PhD in physics." Challenge accepted Mr. Fullerton. Quantum Physics is like the rebel of all science's this is why I am so attracted to the idea! Classical physics says, particle are particles, and waves are waves, and never shall they meet. Particles have an energy E and a momentum vector p. Waves, like light waves, have amplitude A and a wave vector k (where the magnitude of k=2?/?, where ? is the wavelength) that points in the direction the wave is traveling. According to classical physics, that's the end of it. However, in reality things are a bit different. There are random laws. The theories of nature are intellectually intolerable and contradicting. The idea of a random, uncontrollable element in the laws of nature did not sit well with classic physicists. This idea of the arrival of a photon was truly an unpredictable event. The final position of a photon is unpredictable. It is impossible to say where the photon is and what direction it's moving in. This fuzziness deals with the Uncertainty Principle. And by Uncertainty, in no way is this made up numbers. Uncertainty is precise, it is a fact and it is known. (Thank you Hindenburg.) It involves probability measurements, integral calculus, and other fancy mathematics. So this uncertainty dealing with probability could be as simple as flipping a coin 1000 times. Now there is a probability of flipping a coin heads 1000 times, but I wouldn't bet my money on that. It is completely random and unpredictable as of now by scientists. This is kind of what Einstein meant when he said "God doesn't play dice." He flips coins. Just kidding! But there has been some controversy over this with Stephen Hawking challenging Einstein's claim, and presenting an idea which could possibly allow scientists to tell the future. The end of time is the next revolution in physics. Scientist are describing time as something that happens when nothing else does. Others believe if nothing happened, if nothing changed, time would stop. Kind of like if a tree fell in a forest with no one there, would anyone hear it? But this new claim in science questions, and proves time doesn't exist. A timeless universe is intensely temporal. This new theme casts doubt on Einstein's greatest contribution, the space-time continuum. The problem? The great chasm between classical and quantum physics. Einstein's general relativity and quantum mechanics may well spell the end of time. This is the mystery of the universe: multiple worlds, time travel, immortality, and the illusion of motion. This is the most fascinating thing I have ever set my eyes upon. This is the Stern-Gerlach experimental apparatus. The result expected for atoms in an l = 1 state (three components) is shown. The angular momentum is l=0 and z component of that angular momentum is 0. These silver atoms spin up or spin down. Because 46 of the silver's 47 electrons are arranged in a symmetrical cloud, they contribute nothing to the orbital angular momentum of the atom. The 47th electron can be in the 5p state, the angular momentum is l=0 and the z component of angular momentum is 0. It could also be in the 5p state when the angular momentum is l=1, which means the z component of its angular momentum can be -1, 0, or 1. There are two possible directions of spin up or down. Electrons contain intrinsic angular momentum giving us angular momentum that interacts with magnetic field. Angular momentum other than orbital angular momentum is just spin. And depending of the spin of that 47th electron in the atom, there are two possible states of the spin up and down. This is similar to the spin of the earth, you can't stop it. And you also cannot stop the electrons from possessing spin. This goes for other subatomic particles that possess spin, such as protons. Another scary, wonderful thing about quantum mechanics is the interacting of two electrons. Identical particles do not retain their individuality in terms of any measurable, observable quality. You lose the individuality of identical particles as soon as you mix them with similar particles! As soon as you let N identical particles interact, you cannot say which exact is one at r1, r2, r3, r4� Particles obviously have some identity problems. I mean they're just a discrete piece of matter, give them a break. Another cool thing about quantum physics is tunneling. A phenomenon where particle can get through regions that their classically forbidden to go. Are we getting this theme of classic, not being so classy to quantum physics? Mainly what I am trying to say is if I ever fall through the floor due to quantum mechanics, you can have my physics books. The police should really keep their eyes out for photons. They can collide into others, split and then rejoin again! They are tricky things. The basic interaction is called a vertex a fork in the road. A particle proceeds along its world line, until it comes to a fork, but then, instead of choosing one road or the other, the particle splits and turns into two particles, one for each branch. A single electron, spontaneously, without any warning suddenly splits into an electron and a photon, each part is somehow less than the original. Scary concepts from quantum physics: -Probability can be in negatives, but it is nonsense to say, getting heads over tails is a minus one-third chance, it just doesn't make sense. -The complex number, imaginary number, i, is abstract math for the square root minus one. -Black holes are black bodies. -1 light-year is really just a year -Even the coldest object radiates some electromagnetic radiation, as long as they are not absolute zero, which scientist have not yet reached. -If a black hole loses energy, it also loses mass. -Noise is just random unstructured information, like white noise on the screen of a defective TV set, which is why the TV keeps coincidentally turning on in Donnie Darko! Scary. -A dumb hole is a drain hole where the velocity of the flow exceed the speed of sound in water, close to the drain -Mr. Fullerton's hair absorbs every color besides red. -It is possible to have a coin land on its side -It is possible to throw a ball against a wall so many times it goes through "It is impossible as I state it, and therefore I must in some respect have stated it wrong." ~Sherlock Holmes