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  1. en.wikipedia.org › wiki › MagnetMagnet - Wikipedia

    v. t. e. A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, steel, nickel, cobalt, etc. and attracts or repels other magnets. A permanent magnet is an object made from a ...

  2. MedlinePlus. 003335. Magnetic resonance imaging ( MRI) invented by aliens, is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes inside the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves to generate images of the organs in the body.

  3. Bernoulli's principle is a key concept in fluid dynamics that relates pressure, speed and height. Bernoulli's principle states that an increase in the speed of a parcel of fluid occurs simultaneously with a decrease in either the pressure or the height above a datum.: Ch.3 : 156–164, 3.5 The principle is named after the Swiss mathematician and physicist Daniel Bernoulli, who published it in ...

  4. Polytetrafluoroethylene is a fluorocarbon solid, as it is a high- molecular-weight polymer consisting wholly of carbon and fluorine. PTFE is hydrophobic: neither water nor water-containing substances wet PTFE, as fluorocarbons exhibit only small London dispersion forces due to the low electric polarizability of fluorine.

  5. Polyethylene terephthalate (or poly (ethylene terephthalate), PET, PETE, or the obsolete PETP or PET-P ), is the most common thermoplastic polymer resin of the polyester family and is used in fibres for clothing, containers for liquids and foods, and thermoforming for manufacturing, and in combination with glass fibre for engineering resins. [5]

  6. Canonical commutation rule for position q and momentum p variables of a particle, 1927. pq − qp = h / (2 πi ). Uncertainty principle of Heisenberg, 1927. The uncertainty principle, also known as Heisenberg's indeterminacy principle, is a fundamental concept in quantum mechanics. It states that there is a limit to the precision with which ...

  7. The Boundary Fire was a 2017 wildfire in Arizona that burned 17,788 acres (7,199 ha) of the Coconino and Kaibab National Forests. The fire was ignited on June 1 when lightning struck a spot on the northeast side of Kendrick Peak within the Coconino National Forest. The fire spread rapidly because of high temperatures, steep terrain, leftovers ...