Mohr 2015 Metrologia
| Mohr Peter J, Phillips William D (2015) Dimensionless units in the SI. Metrologia 52:40-7. |
Mohr Peter J, Phillips William D (2015) Metrologia
Abstract: The International System of Units (SI) is supposed to be coherent. That is, when a combination of units is replaced by an equivalent unit, there is no additional numerical factor. Here we consider dimensionless units as defined in the SI, e.g. angular units like radians or steradians and counting units like radioactive decays or molecules. We show that an incoherence may arise when different units of this type are replaced by a single dimensionless unit, the unit 'one', and suggest how to properly include such units into the SI in order to remove the incoherence. In particular, we argue that the radian is the appropriate coherent unit for angles and that hertz is not a coherent unit in the SI. We also discuss how including angular and counting units affects the fundamental constants.
• Bioblast editor: Gnaiger E
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- P Fraundorf, Melanie Lipp. Molar standards & information units in the ’new-SI’. 2016. hal-01381003 - https://hal.archives-ouvertes.fr/hal-01381003
