What is plasma? The central element in a fluorescent light is a plasma, a gas made up of free-flowing ions (electrically charged atoms) and electrons (negatively charged particles). Under normal conditions, a gas is mainly made up of uncharged particles. That is, the individual gas atoms include equal numbers of protons (positively charged particles in […]
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Speech to Data To convert speech to on-screen text or a computer command, a computer has to go through several complex steps. When you speak, you create vibrations in the air. The analog-to-digital converter (ADC) translates this analog wave into digital data that the computer can understand. To do this, it samples, or digitizes, the
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Netflix Web Site and Envelope The two most visible parts of the Netflix enterprise are the red mailing envelopes and the Web site. The patented envelope is essentially an ordinary mailing envelope with an extra long, removable flap. This extra length of paper is what lets DVDs make the round trip from the Netflix distribution
OLED Components Like an LED, an OLED is a solid-state semiconductor device that is 100 to 500 nanometers thick or about 200 times smaller than a human hair. OLEDs can have either two layers or three layers of organic material; in the latter design, the third layer helps transport electrons from the cathode to the
The Basics What does it really mean when you “take” a picture with a camera? When you click the shutter, you have frozen a moment in time by recording the visible light reflected from the objects in the camera’s field of view. In order to do that, the reflected light causes a chemical change to
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Relay Construction Relays are amazingly simple devices. There are four parts in every relay: Electromagnet Armature that can be attracted by the electromagnet Spring Set of electrical contacts The following figure shows these four parts in action: In this figure, you can see that a relay consists of two separate and completely independent circuits. The
Project Natal Challenges the Wii On June 1, 2009, Microsoft’s annual E3 press conference announced the development of a motion-sensitive gaming technology code-named Project Natal. The promotional video on YouTube, posted the same day as the press release, portrayed Project Natal as a controller-less way to play games, watch movies and keep in touch with
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Inside a Roomba The Roomba Red is approximately 13 inches (33 cm) in diameter and 3.5 inches (9 cm) tall. An external examination reveals the following parts: Roombas run on a rechargeable NiMH battery. The Roomba Red battery pack is rated at 3 amp-hours and takes about seven hours to fully charge to about 18
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What exactly is a transistor, anyway? Transistors are devices that control the movement of electrons, and consequently, electricity. They work something like a water faucet — not only do they start and stop the flow of a current, but they also control the amount of the current. With electricity, transistors can both switch or amplify
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How it Works: The Science Behind the Magic Way back in the early 1920s, when Léon Theremin worked at the Physico-Technical Institute in St. Petersburg, Russia, he noticed that when he moved his body in or out of an electromagnetic field produced by a radio frequency oscillating circuit, he changed its frequency [source: Harrison]. The
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