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Physics

Science gets colder than absolute zero When an object is heated, its atoms can move with different levels of energy, from low to high. With positive temperatures (blue), atoms more likely occupy low-energy states than high-energy states, while the opposite is true for negative temperatures (red).LMU / MPQ Munich Absolute zero is often thought to be the coldest temperature possible. But now researchers show they can achieve even lower temperatures for a strange realm of "negative temperatures." Oddly, another way to look at these negative temperatures is to consider them hotter than infinity, researchers added. This unusual advance could lead to new engines that could technically be more than 100 percent efficient, and shed light on mysteries such as dark energy, the mysterious substance that is apparently pulling our universe apart. An object's temperature is a measure of how much its atoms move — the colder an object is, the slower the atoms are. Bizarro negative temperatures Wacky physics experiment New kinds of engines
Fundamental Physics

'Time Crystals' Could Upend Physicists' Theory of Time | Wired Science 'Time Crystals' Could Upend Physicists' Theory of Time | Wired Science Physicists plan to create a “time crystal” — a theoretical object that moves in a repeating pattern without using energy — inside a device called an ion trap. Image: Hartmut Häffner In February 2012, the Nobel Prize-winning physicist Frank Wilczek decided to go public with a strange and, he worried, somewhat embarrassing idea. Impossible as it seemed, Wilczek had developed an apparent proof of “time crystals” — physical structures that move in a repeating pattern, like minute hands rounding clocks, without expending energy or ever winding down. Unlike clocks or any other known objects, time crystals derive their movement not from stored energy but from a break in the symmetry of time, enabling a special form of perpetual motion. “Most research in physics is continuations of things that have gone before,” said Wilczek, a professor at the Massachusetts Institute of Technology. Wilczek’s idea met with a muted response from physicists. A Crazy Concept The Big Test
The Incredible Dark Matter Mystery: Why Astronomers Say it is Missing in Action Astronomers have a problem. Whenever they study the large scale structure of the universe, it soon becomes clear that the amount of visible matter cannot possibly generate enough gravity to hold together the structures they can see. Things like galaxy clusters and even galaxies themselves ought to fly apart given the amount of ordinary matter they contain. Something else must be holding these things together. So astronomers have dreamt up the idea of dark matter—mysterious, invisible and non-interacting stuff that fills the universe, generating the gravity necessary to hold everything together. This isn’t a small problem requiring a tiny amount of extra mass. To make the numbers work, astrophysicists tell us that our galaxy ought to be at least 80 per cent dark matter. That means our Solar System ought to be swimming in the stuff. But that raises an important question. But there is another way to look for dark matter—by its gravitational effects on the Solar System itself. The Incredible Dark Matter Mystery: Why Astronomers Say it is Missing in Action
Les enseignants ont kidnappé le débat sur le harcèlement à l'école Ceux qui dénoncent le clip de prévention produit par l'Éducation nationale, jugé «caricatural et méprisant», sont hors sujet. C'est l'histoire d'un rapt. Le 2 novembre, le ministère de l'Education nationale a rendu public le clip de prévention contre le harcèlement scolaire coproduit par Mélissa Theuriau. Presque aussitôt, des profs (et non pas «les profs», comme on l'a lu et entendu) ont manifesté leur mécontentement en dénonçant une «vidéo caricaturale et méprisante». Ils ont surtout, à gros coups de communiqués rageurs publiés par des syndicats pourtant souvent désaccordés, réussi à détourner les projecteurs du sujet principal (la souffrance des enfants harcelés) pour les braquer vers leur propre cause: le supplice enduré par des enseignants se sentant stigmatisés par une vidéo d'une minute qui ne s'adresse même pas à eux. C'est le premier problème de cette réaction. Allégorie Ce que semblent avoir oublié les profs qui s’insurgent contre ce spot, c’est son caractère allégorique. Les enseignants ont kidnappé le débat sur le harcèlement à l'école
A few months ago, my four year-old son went to a classmate's birthday. The party was superhero-themed and the loot bags were packed with cute little superhero trinkets, including temporary tattoos. One little girl, let's call her Izzy, put hers on immediately. "LOOK," Izzy yelled, running up to everyone in turn. The other children and parents in attendance oohed and ahed over her forearm. Later, as we parents were watching our cake-smeared kids run around in a sugar-induced frenzy, one of the other mothers turned to me and said, "Isn't it funny that [your son] loves My Little Pony so much? Not really knowing how to answer, I said, "I don't think it's funny. "Oh, sure," she said. I've been thinking a lot about this episode, along with all the other weird remarks people have made about my kid's love for all things Rainbow Dash. Little girls are, for the most part, taught that women can be anything. We see the devaluation of femininity play out in tons of different ways. We Need To Stop Devaluing Femininity We Need To Stop Devaluing Femininity
Bon, une fois n’est pas coutume, cet article-là, je l’écris surtout avec mes tripes (et en le démarrant je ne sais pas exactement où je vais avec). D’ailleurs ça introduit bien le sujet. D’habitude justement, je rédige mes articles un peu comme des dissertations. Avec un plan (construit à partir d’une liste d’idées) dans la tête, des parties, des sous-partes, des transitions, une intro, une conclusion. Il faut dire que des disserts et des commentaires, comme plein de gens, j’en ai fait depuis mes 15 ans jusqu’à la fin de ma licence. C’est devenu naturel chez moi d’écrire comme ça. D’ailleurs, j’ai souvent été considéré comme un intello, dans ma scolarité. Évidemment, le côté « intello » n’aide pas pour éviter le harcèlement, la mise à l’écart et l’effet plante verte. Et pourtant, au collège comme au lycée, je ne faisais pas réellement partie des bons élèves. C’était une erreur, parce que j’ai (évidemment) continué à ramer dans les matières scientifiques. J'aime : J'aime chargement… Les cancres et les intellos – trolldejardin Les cancres et les intellos – trolldejardin
Physics

About the ToolBox We appreciate any comments and tips on how to make The Engineering ToolBox a better information source. Please contact us by email editor.engineeringtoolbox@gmail.com if You find any faults, inaccuracies, or otherwise unacceptable information. Energy Density for various Storage Forms Energy Density for various Storage Forms
Sugar-powered biobattery has 10 times the energy storage of lithium: Your smartphone might soon run on enzymes As you probably know, from sucking down cans of Coke and masticating on candy, sugar — glucose, fructose, sucrose, dextrose — is an excellent source of energy. Biologically speaking, sugar molecules are energy-dense, easy to transport, and cheap to digest. There is a reason why almost every living cell on Earth generates its energy (ATP) from glucose. Now, researchers at Virginia Tech have successfully created a sugar-powered fuel cell that has an energy storage density of 596 amp-hours per kilo — or “one order of magnitude” higher than lithium-ion batteries. Now, it’s not exactly news that sugar is an excellent energy source. A diagram of the enzymatic fuel cell. Now, however, Zhang and friends at Virginia Tech appear to have built a high-density fuel cell that uses an enzymatic pathway to create a lot of electricity from glucose. Energy densities of various battery types. “15% Maltodextrin”, in dark blue, is the battery being discussed here. Sugar-powered biobattery has 10 times the energy storage of lithium: Your smartphone might soon run on enzymes
Energy Storage Fused Silica Flywheels High tensile strength material allows it to be rotated very fast without flying apart The model with the small yellow disc tends to stop when the crank and connecting rod are in a straight line ('dead' spots) - because sliding the brass knob exerts no turning force on the shaft. In the model with the big yellow flywheel, it is easy to keep the disc turning, once it has started, due to the effect of the flywheel. The mass and the size of the big flywheel helps resist the slowing down of the model as it is turning. Comparative Advantages/Disadvantages of high speed flywheels Flow Batteries: Excitement over flow batteries derives from their attributes, which combine aspects of conventional batteries and fuel cells. Flow batteries are scalable from a few watts and kilowatt-hours to tens or hundreds of megawatts and megawatt-hours. Compressed Air: Has high energy storage capacity compared to the alternatives. One example (in Germany) to date: Ultracapacitors An application: Energy Storage
Introduction STC Motion and Design is a 15-lesson kit intended for students in grade 5. It introduces students to the physics of motion and the importance of technological design. More… Big Ideas This kit is focused on both science content ideas and science process skills. Force as a push or pull More… Foundational Images Along with a variety of drawings, sketches, and multiviews, three of our foundational images are used in conjunction with the STC Motion and Design kit: Vectors , Particles and the Magnifier tool. To get a better idea of how some of these foundational images can be used in the classroom, refer to the Motion and Design roadmap below. Investigation Roadmaps - Motion Investigation Roadmaps - Motion
Physical Sciences

Battaglia’s Chemistry 2015-2016: Unit 2: Atomic Structure Resources | NGSS Chemistry Resources Battaglia’s Chemistry 2015-2016: Unit 2: Atomic Structure Resources | NGSS Chemistry Resources NOTE: This information only represents the general sequencing of resources for lessons, not all of the instructional strategies involved. The Key Essential Questions, Transfer Goals, and Performance Expectations are from the district curriculum map. Unit 2: Atomic Structure From the Big Bang to MRIs Key Essential Questions: What are the characteristic properties and behaviors of waves? Transfer Goals: Students will be able to independently use their learning to Create and use models to illustrate and predict changes in atomic structure.Apply scientific understanding of atomic structure and stability to explain the composition of matter in the universe.Use mathematical and computational thinking to evaluate the relationship between waves and particles. Performance Expectations: Unit Driving Question: How does atomic structure help explain our past, present, and future? Guiding Questions: How are planets and stars formed? Guiding Question: How do we define atomic structure? Other Resources:
Open Source Physics
Physical and Health Education Competencies

Stories We hosted our first PE 9 Health & Careers Expo last week and the event was a huge success! Students posed various health and career questions (to cover the Health and Career 9 curriculum) and we used inquiry to dig deeper. The process was most important and students learned various skills along the way, but the products ended up being very impressive. Students could speak to their questions without reading notes and it was evident their knowledge had increased. I think this shows the importance of voice and choice. My colleague and I took a risk and it ended up paying off. We had an interview group who took video and picture evidence and spoke with attendees and a logistics crew that helped to plan out the entire event.
The Message and the Messenger
A STEP away from the lesson plan. – drowningintheshallow For the first part of my career I spent most of my time honing my knowledge and skills to become more competent in my job as a Teacher of PE. The focus of that competency was efficiency; routines, rules, instruction, subject knowledge and lesson plans. The PE classroom is a dynamic and chaotic place, impacted on by the forever changing environment of resources, weather, facilities and the children themselves. The ability to think on one’s feet and modify what your pupils are doing, based on what you observe, is a key skill to being an effective PE Teacher. David Court suggests Throwing away the plan if perhaps if that is what is needed. Sometimes though throwing out the plan isn’t the best option, but a modification to the lesson plan is. I have found an easy way to change a task or activity within a PE lesson is to use the STEP framework: STEP is an easy framework to use when in the moment of teaching to modify the task to ensure it is at the right level for your pupils. Like this:
Astrophysics (from Greek astron, ἄστρον "star", and physis, φύσις "nature") is the branch of astronomy that deals with the physics of the universe, especially with "the nature of the heavenly bodies, rather than their positions or motions in space."[1][2] Among the objects studied are galaxies, stars, planets, extrasolar planets, the interstellar medium and the cosmic microwave background.[3][4] Their emissions are examined across all parts of the electromagnetic spectrum, and the properties examined include luminosity, density, temperature, and chemical composition. Because astrophysics is a very broad subject, astrophysicists typically apply many disciplines of physics, including mechanics, electromagnetism, statistical mechanics, thermodynamics, quantum mechanics, relativity, nuclear and particle physics, and atomic and molecular physics. In practice, modern astronomical research often involves a substantial amount of work in the realm(s) of theoretical and/or observational physics. Astrophysics
Astrophysics
The circadian rhythm, or circadian clock, is an internal mechanism that drives the 24-hour cycles that tell our bodies when to sleep, wake and eat — and now, new research has found that bacteria living within the gut also have a clock. "We are the directors of that clock, much like the sun directs our own circadian rhythms," said Jiffin Paulose, UK post-doctoral scholar and co-author of the study in PLOS ONE. Paulose and Professor and Chair of the Department of Biology Vincent Cassone found that a certain class of bacteria found in the human gut, Enterobacter aerogenes, expresses circadian patterns because of its sensitivity to melatonin, the hormone produced at night and stimulating sleep. While melatonin is made by the pineal gland, a small gland in the brain, it is also present throughout the gastrointestinal (GI) system. In addition, many foods contain melatonin. The GI system's circadian clock is coordinated to both light and the timing of eating. More information: Jiffin K. Gut bacteria have own circadian clock
Italy's '100 club' to reveal its secrets
This Company Maps Your Genetics to Tell You How You Can Get Stronger
Colour-in geology map of the UK and Ireland
Physical landscapes

Display Photos Database Record
Physical Determinants

Physical Determinants Prezi
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Classes Involving This Determinant
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PHYSICAL EDUCATION

OurUltimateReality
Quantum Jumping - Communicate With Your Subconscious Mind
Eye (cyclone)
Eye (cyclone): Structure
Eye (cyclone): Hazards
Physical Geography

Climate Change Will Make UK Coastline More Dangerous, Expert Says
Italy avalanche: 'Many dead' in hotel Rigopiano in Abruzzo
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astro & quantum physics

physics & consciousness

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Physical Science

Physical and Chemical Changes

Physical Literacy

Health & Physical Education

In the life of a Physical Educator

PHYSICAL GEOGRAPHY OF EUROPE

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