incandescent source

  • 21List of Tesla patents — Below is a list of Tesla patents. Dr. Nikola Tesla was an inventor who obtained around 300 patents [Snezana Sarbo, [http://www.tesla symp06.org/papers/Tesla Symp06 Sarboh.pdfNikola Tesla s Patents] , Sixth International Symposium Nikola Tesla,… …

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  • 22History of electromagnetism — The history of electromagnetism, that is the human understanding and recorded use of electromagnetic forces, dates back over two thousand years ago, see Timeline of electromagnetism. The ancients must have been acquainted with the effects of… …

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  • 23Flashlight — A flashlight (also called an electric torch or torch) is a portable electric spotlight which emits light from a small incandescent lightbulb, or from one or more light emitting diodes (LEDs). The light source is mounted in a housing which… …

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  • 24building construction — Techniques and industry involved in the assembly and erection of structures. Early humans built primarily for shelter, using simple methods. Building materials came from the land, and fabrication was dictated by the limits of the materials and… …

    Universalium

  • 25motion-picture technology — Introduction       the means for the production and showing of motion pictures. It includes not only the motion picture camera and projector but also such technologies as those involved in recording sound, in editing both picture and sound, in… …

    Universalium

  • 26Opto-isolator — This article is about the electronic component. For the optical component, see optical isolator. Schematic diagram of an opto isolator showing source of light (LED) on the left, dielectric barrier in the center, and sensor (phototransistor) on… …

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  • 27Marine aquarium — See also: Reef aquarium A marine aquarium …

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  • 28Luminous efficacy — is a measure of how well a light source produces visible light. It is the ratio of luminous flux to power. Depending on context, the power can be either the radiant flux of the source s output, or it can be the total electric power consumed by… …

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  • 29History of street lighting in the United States — The use of street lighting was first recorded in the Arab Empire from the 9th 10th centuries, [Fielding H. Garrison, History of Medicine :quote| The Saracens themselves were the originators not only of algebra, chemistry, and geology, but of many …

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  • 30Traffic light — The traffic light, also known as traffic signal, stop light, traffic lamp, stop and go lights, robot or semaphore, is a signaling device positioned at a road intersection, pedestrian crossing, or other location. Its purpose is to indicate, using… …

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