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  1. Tesla (unit) - Wikipedia
    • Definition
    • Electric vs. Magnetic Field
    • Conversions
    • Examples

    A particle, carrying a charge of one coulomb, and moving perpendicularly through a magnetic field of one tesla, at a speed of one metre per second, experiences a force with magnitude one newton, according to the Lorentz force law. As an SI derived unit, the tesla can also be expressed as 1. T = V ⋅ s m 2 = N A ⋅ m = J A ⋅ m 2 = H ⋅ A m 2 = Wb m 2 = kg C ⋅ s = N ⋅ s C ⋅ m = kg A ⋅ s 2 {\\displaystyle {\\text{T}}={\\dfrac {{\\text{V}}{\\cdot }{\\text{s}}}{{\\text{m}}^{2}}}={\\dfrac {\\text{N}}{{\\text{A}}{\\cdot }{\\text{m}}}}={\\dfrac {\\text{J}}{{\\text{A}}{\\cdot }{\\text{m}}^{2}}}={\\dfrac {{\\text{H}}{\\cdot }{\\text{A}}}{{\\text{m}}^{2}}}={\\dfrac {\\text{Wb}}{{\\text{m}}^{2}}}={\\dfrac {\\text{kg}}{{\\text{C}}{\\cdot }{\\text{s}}}}={\\dfrac {{\\text{N}}{\\cdot }{\\text{s}}}{{\\text{C}}{\\cdot }{\\text{m}}}}={\\dfrac {\\text{kg}}{{\\text{A}}{\\cdot }{\\text{s}}^{2}}}} (The last equivalent is in SI base units). Where A = ampere, C = coulomb, kg = kilogram, m = metre, N = newton, s = second, H = henry, V = volt, J = joule...

    In the production of the Lorentz force, the difference between electric fields and magnetic fields is that a force from a magnetic field on a charged particle is generally due to the charged particle's movement, while the force imparted by an electric field on a charged particle is not due to the charged particle's movement. This may be appreciated by looking at the units for each. The unit of electric field in the MKS system of units is newtons per coulomb, N/C, while the magnetic field (in teslas) can be written as N/(C⋅m/s). The dividing factor between the two types of field is metres per second (m/s), which is velocity. This relationship immediately highlights the fact that whether a static electromagnetic field is seen as purely magnetic, or purely electric, or some combination of these, is dependent upon one's reference frame(that is, one's velocity relative to the field). In ferromagnets, the movement creating the magnetic field is the electron spin (and to a lesser extent el...

    One tesla is equivalent to:[page needed] 1. 10,000 (or 104) G (Gauss), used in the CGS system. Thus, 10 kG = 1 T (tesla), and 1 G = 10−4T = 100 μT (microtesla). 2. 1,000,000,000 (or 109) γ (gamma), used in geophysics.Thus, 1 γ = 1 nT (nanotesla). 3. 42.6 MHz of the 1H nucleus frequency, in NMR. Thus, the magnetic field associated with NMR at 1 GHz is 23.5 T. One tesla is equal to 1 V⋅s/m2. This can be shown by starting with the speed of light in vacuum, c = (ε0μ0)−1/2, and inserting the SI values and units for c (2.998×108 m/s), the vacuum permittivity ε0 (8.85×10−12 A⋅s/(V⋅m)), and the vacuum permeability μ0 (12.566×10−7 T⋅m/A). Cancellation of numbers and units then produces this relation. For the relation to the units of the magnetising field (ampere per metre or Oersted), see the article on permeability.

    The following examples are listed in ascending order of field strength. 1. 3.2 × 10−5 T (31.869 μT) – strength of Earth's magnetic fieldat 0° latitude, 0° longitude 2. 5 × 10−3 T (5 mT) – the strength of a typical refrigerator magnet 3. 0.3 T – the strength of solar sunspots 4. 1.25 T – magnetic flux density at the surface of a neodymium magnet 5. 1 T to 2.4 T – coil gap of a typical loudspeaker magnet 6. 1.5 T to 3 T – strength of medical magnetic resonance imagingsystems in practice, experimentally up to 17 T 7. 4 T – strength of the superconducting magnet built around the CMS detector at CERN 8. 5.16 T – the strength of a specially designed room temperature Halbach array 9. 8 T – the strength of LHCmagnets 10. 11.75 T – the strength of INUMAC magnets, largest MRI scanner 11. 13 T – strength of the superconducting ITERmagnet system 12. 14.5 T – highest magnetic field strength ever recorded for an accelerator steering magnet at Fermilab 13. 16 T – magnetic field strength required t...

  2. File:Theater commercial, electric refrigerator, 1926.ogv - Wikipedia,_electric...
    • Notes
    • Subjects
    • Medium
    • Repository

    Copyright: no reg. Probable distribution date from original nitrate film edge date code. Duration: 0:43 at 18 fps. Title graphic: "Buy an electric refrigerator" -- Medium shot of woman opening a refrigerator and removing a dish -- Graphic: "An electric refrigerator provides convenience and comfort, safeguards health and is a real economy" -- Scrolling graphic: "See all makes at the refrigerator show, 933 Liberty Ave., April 5th to 19th, 11:00 a.m. to 11:00 p.m., admission free! Electric League of Pittsburgh." NCN007341; Buy an electric refrigerator. Received: 2/18/86 from LC film lab; ref print; preservation, NTM 203; AFI/Kalinowski (Eugene) Collection.

    Advertising--Electric household appliances--Pennsylvania--Pittsburgh.
    Trade shows--Pennsylvania--Pittsburgh.
    Pittsburgh (Pa.)--Manufactures.

    1 reel of 1 (ca. 70 ft.) : si., b&w ; 35 mm. ref print. 1 reel of 1 (ca. 70 ft.) : si., b&w ; 35 mm. dupe neg.

    Library of Congress Motion Picture, Broadcasting and Recorded Sound Division Washington, D.C. 20540 USA

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