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non SI unit
subject			fact

non SI unit	has value in SI unit
	has definition not an SI unit, but an important and widely used unit
	is a kind of unit
unit	has historical origin
	represents

Kinds of non SI unit :

• angstrom (6 facts) (Å) - A unit of length used when expressing wavelengths.
• astronomical unit (9 facts) (AU) - Mean distance between the Earth and the Sun: 1.495985 × 10¹¹ m., The AU is the preferred unit for distances within the solar system. Mercury, the innermost planet, lies on average 0.39 AU from the Sun; Pluto, normally the farthest planet, lies on average 39.5 AU from the Sun., The mean distance between the Earth and the Sun. The astronomical unit is defined as the length of the radius of the unperturbed circular orbit of a body of negligible mass moving around the Sun with a sidereal angular velocity of 0.017202098950 radian per day of 86400 ephemeris seconds. AU = 1.496 × 10¹³ cm ≈ 500 lt-sec., The mean distance from the earth to the sun, equal to 92.81 million miles or 499.012 light-seconds., The radius of a circular orbit in which a body of negligible mass, and free of perturbations, would revolve around the Sun in 2π / k days, where k is the Gaussian gravitational constant. This is slightly less than the semi-major axis of the Earth's orbit.
• bel (3 facts) (B)
• day (2 kinds, 12 facts) (d) - An interval of 86400.51 seconds, unless otherwise indicated.
• degree (angle) (3 facts) (°)
• electron volt (10 facts) (eV, eV) - Unit employed to indicate the energy of a charged particle in terms of the energy received by the charge on an electron due to a potential difference of one volt. An approximate value (1 in 10⁴) for the energy of electromagnetic radiation expressed in electron volts is given by 1234 / λ, where λ is the wavelength in nanometres. In recent years it has become customary to write MeV and GeV for mega (10⁶) and giga (10⁹) electron volts. In the USA 10⁹ electron volts are often written as BeV, the letter B being used in this case as an abbreviation for the American billion (10⁹), but in 1948 the International Union of Pure and Applied Physics disapproved of the use of BeV and expressed a preference for GeV or 10⁹ eV. The electron volt was called the equivalent volt when it was originally introduced in 1912., Unit of energy used in atomic and nuclear physics; the kinetic energy acquired by one electron in passing through a potential difference of 1 volt in vacuum. Sometimes used as a unit of mass (see rest-mass energy)
• hour (3 facts) (h)
• liter (3 facts) (L)
• metric ton (3 facts) (t)
• minute (angle) (4 facts) (', arc minute)
• minute (time) (3 facts) (min)
• neper (3 facts) (Np)
• second (angle) (4 facts) (", arc second)
• unified atomic mass unit (3 facts) (u)