Units - 1. UNITS Measurements of physical quantities take...

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1. UNITS Measurements of physical quantities take place by means of a comparison with a standard. For example: a meter stick, a weight of 1 kilogram, etc. The base units that will be used in this course are: meter (m) : One meter is equal to the path length traveled by light in vacuum during a time interval of 1/299,792,458 of a second. kilogram (kg) : One kilogram is the mass of a Platinum-Iridium cylinder kept at the International Bureau of Weights and Measures in Paris. second (s) : One second is the time occupied by 9,192,631,770 vibrations of the light (of a specified wavelength) emitted by a Cesium-133 atom. A unit that is being used as a base unit must be both accessible and invariable. The original meter bar kept in Paris was not very accessible (this is still true for the kilogram). In addition, the length of the standard bar is temperature dependent. The definition of the meter in terms of the number of wavelengths of a particular atomic transition in Krypton-86 made the meter more
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Units - 1. UNITS Measurements of physical quantities take...

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