If it's written as "0.5 ampere", shouldn't we write "0.5 hour" and not "0.5 hours"?


1 Answer 1


It should be "0.5 amperes" and "0.5 hours". It is a rule in English that for any value other than 1, the units should be written in the plural form if they are being spelled out. If you are using abbreviations for units, however, they should remain singular in spelling (e.g. "0.5 A" not "0.5 As").

  • Any value except 1 or -1, but otherwise I agree with you.
    – nnnnnn
    Oct 26, 2020 at 9:21
  • Imagining a current of -0.5 A is hard. Oct 26, 2020 at 12:34
  • Please add supporting references, linked and attributed, to answers. But note that many questions are duplicates; this has certainly been answered before, and ELU aims to avoid bloat. Oct 26, 2020 at 15:35
  • @MichaelHarvey - I was referring to the general rule, but in the context of electricity volts can certainly have negative values and that may be directly relevant for somebody who asked about amperes.
    – nnnnnn
    Oct 26, 2020 at 23:08
  • Voltage is measured relative to some reference point. You can't have less than zero current. Oct 27, 2020 at 7:02

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