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Articles on "Electricity"

Articles on "Electricity"
Why three prongs?Why do wall outlets have three holes? "Grounding" and safety. Right Angle CircuitryDo Lenz' Law and the Right Hand rule still work... after you've been turned INSIDE OUT by that greasy black Fog? "Static Electric" misconceptionsA list of things which gave me a warped view of Electrostatics. Speed of "Electricity"? Triboelectric Series If a cat gets trapped in a clothes dryer full of nylon pantyhose, which way do the electrons flow? Where does EM energy flow in a circuit? How Scientists Define the word "Electricity" Quotes from J.C. Barriers to Understanding ElectricityTwenty misconceptions which prevented me from understanding simple electrical science as a student. "Static" Electricity is really just high voltage.Scuff on the rug, then measure your body voltage. Electricity mistakes and 'nitpicking' also How SHOULD we teach Electricity? "Static" sparks Doorknob sparks and zapping yourself on the car door... and people who suffer from an "electric shock" disease. Related:  physicsResources physicsResources technology

Dimensions Home A film for a wide audience! Nine chapters, two hours of maths, that take you gradually up to the fourth dimension. Mathematical vertigo guaranteed! Background information on every chapter: see "Details". Click on the image on the left to watch the trailer ! Free download and you can watch the films online! The film can also be ordered as a DVD. This film is being distributed under a Creative Commons license. Now with even more languages for the commentary and subtitles: Commentary in Arabic, English, French, German, Italian, Japanese, Spanish and Russian. Film produced by: Jos Leys (Graphics and animations) Étienne Ghys (Scenario and mathematics) Aurélien Alvarez (Realisation and post-production)

Virtual Library: CAD CAD software is commonly used for drafting architectural and engineering drawings and for making technical illustrations of any kind. If you are a professional associated with design or drafting or would just like to widen your knowledge about CAD applications, then you will find this section of informative and useful. CAD enables you to prepare fast and accurate drawings. This section of Virtual Library is devoted to CAD education. Join online AutoCAD Training - Learn more...

Disappearing Glass Rods: Reflection, Refraction & Light Science Activity Disappearing Glass Rods You can make glass objects disappear. Glass objects are visible because they reflect some of the light that shines on them and bend or refract the light that shines through them. Wesson™ oil. (1 minute or less) Pour some Wesson™ oil into the beaker. (15 minutes or more) Immerse a glass object in the oil. Experiment with a variety of glass objects, such as clear marbles, lenses, and odd glassware. You can make an eyedropper vanish before your eyes by immersing it and then sucking oil up into the dropper. Immerse the magnifying lens in the oil. When light traveling through air encounters a glass surface at an angle, some of the light reflects. When light passes from air into glass, it slows down. The smaller the difference in speed between two clear materials, the less reflection will occur at the boundary and the less refraction will occur for the transmitted light. Wesson™ oil has nearly the same index of refraction (n) as Pyrex® glass (n = 1.474).

Newton Rocket Car Summary The purpose of this activity is to demonstrate Newton's third law of motion — which states that every action has an equal and opposite reaction — through a small wooden car. The Newton cars show how action/reaction works and how the mass of a moving object affects the acceleration and force of the system. Engineering Connection Engineers will often build a model to demonstrate and study a law of science. Educational Standards Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards. All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standard Network (ASN), a project of JES & Co. In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc. Pre-Req Knowledge Learning Objectives Materials List Each group needs:

IoHT :: 110+ Variations of the Second Law of Thermodynamics Questions about these second law variations? Know of other second law definitions? Copyright © Institute of Human Thermodynamics and IoHT Publishing Ltd. All Rights Reserved [1] Hippocrates (c. 440 BC). NEED SOURCE [email me if you have it] [2] Lavoisier, A. (1789). [3-4] Carnot, S. (1824). [5-8] Clausius, R. (1850). [9] Kelvin, L. (1852). [10] Kelvin, L. (1852). [11] Kelvin, L. (1852). [12] Kelvin, L. (1852). [13] Kelvin, L. (1852). the Philosophical Magazine, October, 1852; also Mathematical and Physical Papers, vol. i, art. 59. [14] Clausius, R. (1865). [15] Kelvin & Planck. (1879). [16-17] Planck. [18] Caratheodory, C. (1908). [19-21] Fermi, E. (1936). [22-23] Bridgman, P. (1941). [24] Keenan, J. (1941). [25-26] Klotz. [27] Fritz, A. (1959). [28] King, A. (1962). [29-30] Lee, J. & Sears, F. (1963). [31-32] Bazarov, I. (1964). [33] Bent, H. (1965). [34] Hatsopoulos, G. & Keenan, J. (1965). [35-37] Kern, R. & Weisbrod, A. (1967). [38] Battino, R. & Wood, S. (1968). [58] Ebbing (1990). 1.

Transformers In the photograph, note that the coil on the left has fewer coils than that at right (the insets show close-ups). The sketch and circuit show a step-up transformer. To make a step-down transformer, one only has to put the source on the right and the load on the left. (Important safety note: for a real transformer, you could only 'plug it in backwards' only after verifying that the voltage rating were appropriate.) The core (shaded) has high magnetic permeability (ie a material that forms a magnetic field much more easily than free space does, due to the orientation of atomic dipoles). Vp = − Np.dφ/dt . VpIp = VsIs, whence Is/Ip = Np/Ns = 1/r. So you don't get something for nothing: if you increase the voltage, you decrease the current by at least the same factor. In some cases, decreasing the current is the aim of the exercise.

Optics For Kids - The Optical Society: Exploring the Science of Light Remote controls for devices like televisions, cable boxes, and DVD players typically operate in the infrared. On the front of the remote is a light emitting diode (LED) that produces light in the infrared region. The light flashes quickly to produce a sequenced pattern, which the device being controlled then reads and interprets as a command. Required Materials TV/cable/DVD remote control Webcam or camera phone Activity Directions Point a cheap CCD camera (camera phone or webcam) at the LED on the front of the remote control and view the image on the phone/computer. Here's What's Happening Digital cameras are typically made from silicon CCD’s, which can detect light from the visible out to the near end of the infrared.

NAROM -Praktiske aktiviteter NAROM har et bredt spekter av spennende praktiske lab-øvelser som tilbys ved ulike kurs og aktiviteter. I mange av øvelsene blir den unike infrastrukturen ved Andøya Space Center benyttet slik at kursdeltakerne får sjansen til å gjennomføre øvelser som ikke ville vært mulig å gjennomføre ved lærestedet de kommer fra. Her kommer en oversikt over noen av NAROMs mest sentrale øvelser. Rakettverksted Det er tre forskjellige slags raketter som kan bygges i rakettverkstedet: modellrakett, papirrakett og vannrakett. NAROM velger av disse alt etter behov i det respektive kurset. Det er standard at høyde og avstand av rakettskuddene måles. ModellrakettRakettene lages av byggesett og brukes sammen med svartkkruttmotor (papirraketter og vannraketter bruker overtrykk). Last ned øvelsen: Papirrakettøvelse med mal (pdf)Last ned byggeinstruksjoner for rampe: Utskytningsrampe mal (pdf) VannrakettVannrakett er en av de enkleste måtene å bygge en rakett på. Last ned øvelsen: Vannrakettøvelse (pdf)

Special Relativity Special Relativity These pages are ok as far as they go, but they are missing the planned highlight, to show you what things actually look like when you travel at near the speed of light. I hope to have the opportunity to develop these pages further as time permits. Meanwhile, these pages comprise an animated introduction to the elements of Special Relativity. And don't miss Prasenjit Saha's Interactive Lorentz Transformations. © 1998, 1999 Andrew Hamilton. Forward to The Postulates of Special Relativity Hey, get me back to Falling into a Black Hole Unless otherwise stated, clicking on images gives you enlarged versions thereof, which may be easier to view in a classroom environment. Special Relativity: Index Andrew Hamilton's Homepage Other Relativity and Black Hole links

Eddy current brake An eddy current brake of a German ICE 3 in action. An eddy current brake, like a conventional friction brake, is responsible for slowing an object, such as a train or a roller coaster. However, unlike electro-mechanical brakes, which apply mechanical pressure on two separate objects, eddy current brakes slow an object by creating eddy currents through electromagnetic induction which create resistance, and in turn either heat or electricity. Construction and operation[edit] Circular eddy current brake[edit] Principle of the linear eddy current brake Japanese Shinkansen trains had employed circular eddy current brake system on trailer cars since 100 Series Shinkansen. Linear eddy current brake[edit] The principle of the linear eddy current brake has been described by the French physicist Foucault, hence in French the eddy current brake is called the "frein à courants de Foucault". The braking energy of the vehicle is converted in eddy current losses which lead to a warming of the rail. K.D.

Can you make a rainbow disappear? What you need: A colour print out of the colour wheel above Glue Cardboard Scissors Pencil How you do it: Print out the colour wheel above. Glue the colour wheel to a sheet of cardboard. Once the glue is dry, pierce the the middle of the colour wheel with scissors (ask a parent or guardian for help here). Insert a pencil through the hole until the colour wheel is about a third of the way along the pencil. Spin the disc and watch what happens... Did you see the colours merge into white? Watch this video to see a different Newton's disc being made: Or go to YouTube. Thanks to Planet Scicast for pointing us in the direction of the brilliant Arvind Gupta.