physics and teaching
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* Magnetic field is meassured each 10 seconds and compensated for temperature drift. * Upload data to COSM (Pachube) * RTC is syncronized to internet time server in regular intervals
Applications Thermal imaging can be used to document heat/AC leaks from insulation gaps on a building's facade, reveal warmer ground water inflows (either fresh or chemical-laden) or "thermal pollution" from industrial processes entering ocean-temperature waterbodies, as well as identify areas on the human body experiencing infection or stress (includes epidemiological applications). Community applications so far include both a "heat-busters" program in East Harlem and a "forensic" water quality monitoring program in the Gowanus Canal .
Aerodynamics Drag Coefficient A dimensionless value that allows the comparison of shape and orientation of different bodies. Kinematic Viscosity
The electromagnetic waves that compose electromagnetic radiation can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields. This diagram shows a plane linearly polarized EMR wave propagating from left to right. The electric field is in a vertical plane and the magnetic field in a horizontal plane. The two types of fields in EMR waves are always in phase with each other, and no matter how powerful, have a ratio of electric to magnetic intensity which is fixed and never varies Electromagnetic radiation ( EM radiation or EMR ) is a form of energy emitted and absorbed by charged particles which exhibits wave-like behavior as it travels through space. EMR has both electric and magnetic field components, which stand in a fixed ratio of intensity to each other, and which oscillate in phase perpendicular to each other and perpendicular to the direction of energy and wave propagation .
With the general theory of relativity, in which Einstein managed to reconcile relativity and gravitation, he had to discard the traditional physics worldview, which saw space as merely a stage on which the events of the world unfold. Instead, space-time is a dynamic entity, which is distorted by any matter that is contained in it, and which in turn tells that matter how to move and evolve. This interaction between spacetime and matter is described by Einstein's geometric, relativistic theory of gravity. The consequences of that theory are spectacular.
Demoing the SudoGlove at the 2011 Open Hardware Summit What is the SudoGlove? The SudoGlove is a gesture controller that can be easily interfaced with hardware or software via a wireless connection. The glove implements an array of sensors plus filtering circuitry and mathematical analysis firmware to derive state values for each sensor and transmits them to an authorized receiver. I have used the glove to drive an RC car, to synthesize music, to manipulate openGL video, to control arbitrary processing software, and to control performance lighting effects. You can see videos and examples of these interfaces below.
Islamic Astronomy: Astronomical instruments Muslim astronomers developed a number of astronomical instruments, including several variations of the astrolabe, originally invented by Hipparchus in the 2nd century BCE, but with considerable improvements made to the device in the Muslim world. These instruments were used by Muslims for a variety of purposes related to astronomy, astrology, horoscopes, navigation, surveying, timekeeping, Qibla, Salah, etc. Astrolabes Brass astrolabe by Muhammad al-Fazari in the 8th century. Earliest surviving astrolabe in 315 AH (927-928 CE).
This circuit is an astable multivibrator , or oscillator . The two transistors are cross-coupled in such a way that the circuit switches back and forth between two states. In one state, the base of Q1 is about one diode drop above ground, allowing a base current to flow. This keeps Q1 switched on, in saturation mode, allowing a current to flow through the collector, keeping Q1's collector voltage low, and discharging C1.
Semiconductor's Magnetic Movie written by Douglas Kahn : In 1744 a simple experiment was conducted in Sweden to reproduce the underlying cause of the Aurora Borealis in a laboratory, what we would now think of as a room. A small hole in a shade "the size of a large pea" let through a ray of sunlight that then was refracted through a prism. The small patch of light broken into a spectrum of colours then traveled through a medium of turbulent air directly above a warmed glass of aquavit. The resulting image landed on a screen a few short feet away and looked like what was seen dancing in the sky on many long Swedish nights, nature's sublime entertainment in the real pre-history of cinema. The experiment concluded that the aurora was caused by a refraction of light through volatile vapors.
Cool Experiments with Magnets This web site is devoted to magnetism and the cool experiments you can do with permanent magnets and electro-magnets. Some of the experiments are very basic - things you've done since second grade.
An impressive homemade wall climbing system from a simple vacuum cleaner was created by a scientist from BBC. After being bitten by a radioactive spider, the mild-mannered Peter Parker in the Spiderman movies and comics finds himself able to climb up the side of buildings. The enterprising scientist Jem Stansfield got the same effect in real life from the two vacuum cleaners purchased at Tesco. From the video below, he demonstrated his Spiderman Prowess by climbing up the 120 feet front wall of BBC Television center as he documented his experience. The image below shows how he used the suction power of a modified vacuum cleaner motor to hold his weight on the wall.
You don't have to check the internet to find out when the Northern Lights might be visible from where you are, you can make your own magnetometer to act as a detector. You needn't be a rocket scientist to do it! There are two different detectors: The pop-bottle-detector is very easy to make, and very easy to use. The compass-detector uses a simple h4_op_amp circuit with a negative feedback loop and is suitable to be used with a data logging device, or other voltage measuring device. See further information about where to obtain the parts and details of the original designs.
Solar power technology in action. In one way or another, almost every form of energy we use originates as energy from the Sun. Solar energy directly powers photovoltaic cells and thermal collectors.