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v9vyesterday at 10:36 AM1 replyview on HN

For it to be an SI unit, shouldn't you be able to express it in terms of the 7 SI base units?


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tuetuopayyesterday at 11:29 AM

The requests would be a dimension-less quantity. There are a few examples of what those are and how they fit in:

- The frames in frames per second are dimensionless, thus the SI unit for FPS is frames/s. When the frames are periodic, such as monitor refresh rates are, the unit is Hz.

- Percentages are dimensionless quantities too, produced by divinding two quantities of the same dimension (ie unit). CPU%? That’s "busy second per second", which is dimensionless, and expressed as a percentage.

A dimensionless quantities don’t have any physical backing reality in terms of the, well, dimension in which you could measure it. Time, space, mass, etc.

Fun fact: angles are dimensionless! Both degrees and radians are just shorthands as divisions of the unit circle.

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