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  1. Neptune - Wikipedia › wiki › Neptune

    Neptune is the eighth and farthest known Solar planet from the Sun.In the Solar System, it is the fourth-largest planet by diameter, the third-most-massive planet, and the densest giant planet.It is 17 times the mass of Earth, slightly more ...

    • 5.43 km/s
    • 0.6713 day, 16 h 6 min 36 s
    • 2.68 km/s (9,650 km/h)
    • 164.8 yr, 60,195 days, 89,666 Neptunian solar days
  2. Coca-Cola - Wikipedia › wiki › Coca-Cola

    Coca-Cola, or Coke, is a carbonated soft drink manufactured by The Coca-Cola Company.Originally marketed as a temperance drink and intended as a patent medicine, it was invented in the late 19th century by John Stith Pemberton and was bought out ...

  3. Robot - Wikipedia › wiki › Robot

    Machine capable of carrying out a complex series of actions automatically. This article is about mechanical robots. For software agents, see Bot. For other uses of the term, see Robot (disambiguation). ASIMO (2000) at the Expo 2005. Articulated ...

  4. Microscope - Wikipedia › wiki › Microscope
    • History
    • Types
    • External Links

    Although objects resembling lenses date back 4,000 years and there are Greek accounts of the optical properties of water-filled spheres (5th century BC) followed by many centuries of writings on optics, the earliest known use of simple microscopes (magnifying glasses) dates back to the widespread use of lenses in eyeglasses in the 13th century. The earliest known examples of compound microscopes, which combine an objective lens near the specimen with an eyepiece to view a real image, appeared in Europe around 1620. The inventor is unknown although many claims have been made over the years. Several revolve around the spectacle-making centers in the Netherlands including claims it was invented in 1590 by Zacharias Janssen (claim made by his son) and/or Zacharias' father, Hans Martens, claims it was invented by their neighbor and rival spectacle maker, Hans Lippershey (who applied for the first telescope patent in 1608), and claims it was invented by expatriate Cornelis Drebbel who was...

    Microscopes can be separated into several different classes. One grouping is based on what interacts with the sample to generate the image, i.e., light or photons (optical microscopes), electrons(electron microscopes) or a probe (scanning probe microscopes). Alternatively, microscopes can be classified based on whether they analyze the sample via a scanning point (confocal optical microscopes, scanning electron microscopes and scanning probe microscopes) or analyze the sample all at once (wide field optical microscopes and transmission electron microscopes). Wide field optical microscopes and transmission electron microscopes both use the theory of lenses (optics for light microscopes and electromagnet lenses for electron microscopes) in order to magnify the image generated by the passage of a wave transmitted through the sample, or reflected by the sample. The waves used are electromagnetic (in optical microscopes) or electron beams (in electron microscopes). Resolutionin these mic...

  5. Leonardo da Vinci - Wikipedia › wiki › Leonardo_da_Vinci

    Leonardo da Vinci, [b] properly named Leonardo di ser Piero da Vinci (Leonardo, son of ser Piero from Vinci), [8] [9] [c] was born on 15 April 1452 in, or close to, the Tuscan hill town of Vinci; Florence was 20 miles away. [10] [11] [d] He was ...

  6. Electric generator - Wikipedia › wiki › Electric_generator
    • Terminology
    • History
    • Specialized Types of Generator
    • Common Use Cases
    • Equivalent Circuit

    Electromagneticgenerators fall into one of two broad categories, dynamos and alternators. 1. Dynamos generate pulsing direct current through the use of a commutator. 2. Alternators generate alternating current. Mechanically a generator consists of a rotating part and a stationary part: 1. Rotor: The rotating part of an electrical machine. 2. Stator: The stationary part of an electrical machine, which surrounds the rotor. One of these parts generates a magnetic field, the other has a wire winding in which the changing field induces an electric current: 1. Field winding or field (permanent) magnets: The magnetic field-producing component of an electrical machine. The magnetic field of the dynamo or alternator can be provided by either wire windings called field coils or permanent magnets. Electrically-excited generators include an excitation system to produce the field flux. A generator using permanent magnets (PMs) is sometimes called a magneto, or a permanent magnet synchronous gene...

    Before the connection between magnetism and electricity was discovered, electrostatic generators were invented. They operated on electrostatic principles, by using moving electrically charged belts, plates, and disks that carried charge to a high potential electrode. The charge was generated using either of two mechanisms: electrostatic induction or the triboelectric effect. Such generators generated very high voltage and low current. Because of their inefficiency and the difficulty of insulating machines that produced very high voltages, electrostatic generators had low power ratings, and were never used for generation of commercially significant quantities of electric power. Their only practical applications were to power early X-ray tubes, and later in some atomic particle accelerators.

    Direct current

    A dynamo uses commutators to produce direct current. It is self-excited, i.e. its field electromagnets are powered by the machine's own output. Other types of DC generators use a separate source of direct current to energize their field magnets.

    Power station

    A power station, also referred to as a power plant or powerhouse and sometimes generating station or generating plant, is an industrial facility for the generation of electric power. Most power stations contain one or more generators, a rotating machine that converts mechanical power into three-phase electric power. The relative motion between a magnetic field and a conductor creates an electrical current. The energy source harnessed to turn the generator varies widely. Most power stations in...


    An engine-generator is the combination of an electrical generator and an engine (prime mover) mounted together to form a single piece of self-contained equipment. The engines used are usually piston engines, but gas turbines can also be used, and there are even hybrid diesel-gas units, called dual-fuel units. Many different versions of engine-generators are available - ranging from very small portable petrolpowered sets to large turbine installations. The primary advantage of engine-generator...

    Human powered electrical generators

    A generator can also be driven by human muscle power (for instance, in field radio station equipment). Human powered electric generators are commercially available, and have been the project of some DIY enthusiasts. Typically operated by means of pedal power, a converted bicycle trainer, or a foot pump, such generators can be practically used to charge batteries, and in some cases are designed with an integral inverter. An average "healthy human" can produce a steady 75 watts (0.1 horsepower)...

    An equivalent circuit of a generator and load is shown in the adjacent diagram. The generator is represented by an abstract generator consisting of an ideal voltage source and an internal impedance. The generator's V G {\\displaystyle V_{\\text{G}}} and R G {\\displaystyle R_{\\text{G}}} parameters can be determined by measuring the winding resistance (corrected to operating temperature), and measuring the open-circuit and loaded voltage for a defined current load. This is the simplest model of a generator, further elements may need to be added for an accurate representation. In particular, inductance can be added to allow for the machine's windings and magnetic leakage flux,but a full representation can become much more complex than this.

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