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Light-emitting diode

A light-emitting diode (LED) is a semiconductor light source.[3] LEDs are used as indicator lamps in many devices and are increasingly used for other lighting. Introduced as a practical electronic component in 1962,[4] early LEDs emitted low-intensity red light, but modern versions are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness. When a light-emitting diode is forward-biased (switched on), electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence and the color of the light (corresponding to the energy of the photon) is determined by the energy gap of the semiconductor. LEDs are often small in area (less than 1 mm2), and integrated optical components may be used to shape its radiation pattern.[5] LEDs present many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved robustness, smaller size, and faster switching. LEDs powerful enough for room lighting are relatively expensive and require more precise current and heat management than compact fluorescent lamp sources of comparable output. Light-emitting diodes are used in applications as diverse as aviation lighting, automotive lighting, advertising, general lighting, and traffic signals. LEDs have allowed new text, video displays, live video, and sensors to be developed, while their high switching rates are also useful in advanced communications technology. Infrared LEDs are also used in the remote control units of many commercial products including televisions, DVD players, and other domestic appliances.

The BG-BL01 is a combination device, both solar battery charger and emergency LED Light. The solar power come courtesy of a HIT Solar panel, the same type of current generation panels that are found on homes. The BG-BL01 also comes equipped with a USB port, two AA Battery Charger slots and three LED lights.

Z-Wave is a wireless communications protocol designed for home automation, specifically to remotely control applications in residential and light commercial environments. The technology uses a low-power RF radio embedded or retrofitted into home electronics devices and systems, such as lighting, home access control, entertainment systems and household appliances.

Metre From Wikipedia, the free encyclopedia   (Redirected from Meter) Jump to: navigation, search This article is about the unit of length. For other uses of "metre" or "meter", see meter (disambiguation). 1 metre = SI units 100 cm 1000 mm US customary / Imperial units 3.2808 ft 39.370 in The metre (meter in the US), symbol m, is the base unit of length in the International System of Units (SI). Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole (at sea level), its definition has been periodically refined to reflect growing knowledge of metrology. Since 1983, it has been defined as "the length of the path travelled by light in vacuum during a time interval of 1 ⁄ 299,792,458 of a second.[1]

Second From Wikipedia, the free encyclopedia Jump to: navigation, search This article is about the unit of time. For other uses, see Second (disambiguation). A light flashing approximately once per second The second (SI unit symbol: s) is the International System of Units (SI) base unit of time[1] and also a unit of time in other systems (abbreviated s or sec[2]). Between 1000 (when al-Biruni used seconds) and 1960 the second was defined as 1/86,400 of a mean solar day (that definition still applies in some astronomical and legal contexts).[3][4] Between 1960 and 1967, it was defined in terms of the period of the Earth's orbit around the Sun,[5] but it is now defined more precisely in atomic terms. Seconds may be measured using mechanical, electric or atomic clocks.

Lesson 1Introduction

Lesson 2Filter image results by color Activity Lesson 3How search works Activity Lesson 4The art of keyword choices Activity Lesson 5Word order matters Activity Lesson 6Finding text on a web page Activity Introduction Text Version Next

The U49325 Sun Runner Stirling Engine is a solar-powered Stirling Engine which offers a dramatic demonstration of energy conversion.   This motor and its parabolic mirror can be attached to any conventional camera tripod. When properly aimed at the sun, the polished aluminum parabolic mirror focuses incoming solar energy on the heat cap of the engine, which is converted to rotary motion. Unit comes complete with motor, parabolic mirror, and wrenches. Standard camera tripod is not supplied. This engine is completely assembled and ready to run. Each unit is test run at the factory prior to shipping. Motor runs at 2,000 RPM and up. This engine can also run as a horizontal engine with an alcohol burner. Demonstrate this exciting method of harnessing the sun’s clean and renewable energy to your students.  Weight: 6.00 lbs Dimensions: Engine: 8.25 x 3 inches (L x W) Flywheel: 3.25 inchesParabolic Mirror: 18 inch diameterPlease note that this item is designed to demonstrate the operating principles of a Stirling engine for educational use and is not designed for power production.  It can potentially be coupled with a generator for producing very small amounts of electricity but is incapable of powering anything beyond a small light bulb or LED.

What is My N3RD? My N3RD (Pronounced Nerd) turns your smartphone into a remote control for every gadget, vehicle and appliance you own. It works with the My N3RD app to upgrade ANY switch into a wireless controlled, programmable, and automatic smart switch, updating all of your devices into intelligent connected ones. Connect and control devices directly. No internet connection or router required.   Works with DC and mobile applications such as Cars, RVs, and boats. With My N3RD, you aren’t just limited to home appliances. Connects to any switch, enabling you to upgrade virtually anything— not just simple appliances like fans and lights. Simple setup. You only need to configure functions in the App once, and you can reuse them again and again. My N3RD is equipped with two relays and two inputs that can be used with external switches and physical switches to create a wide variety of uses. My N3RD is smart. You can program My N3RD to act without your intervention. Use the app to set timers for appliances and electronics. Although My N3RD has direct connect capability, it can also be connected through your home WiFi so you can control your devices from anywhere. Upgrade anything to an Internet of Things device.

Brain simulates actions in stories as a person reads: study

What scientists discovered was that parts of the brain associated with certain activities described in the story would light up as the person read those sections.

This study suggests that readers do mental simulation when they comprehend a story,"

make thoses phone events visible somewhere else, on your wearable, in your living room, on your robot, in your office or where ever you want it to occur? Or would you like to use your smartphone sensors, like the accelerometer, light sensor, compass or your touchscreen to control other devices? 'android meets arduino' is a toolkit, basically consisting of an Android application and an Arduino library which will help you to interface with your phone in a new dimension. You can build your own interfaces almost without any programming experience.

The unit is light weight (2.5 lb), portable, low cost ($10-$20) and can be used to recharge single cell batteries at from 1-3.5 amps. It can be made from a cordless electric drill in a primitive environment. The simplest way of how to make a hand crank DC generator using a standard 12, 14.4 or 18 Volt Cordless drill

With no modification hook an alligator clip jumper to the two charging terminals (on the bottom that the battery plugs into). See picture below. Note that when a 14.4 Volt drill is laid down pointing to the left then the upper terminal is most likely to be the plus and the lower terminal the minus for these units.