Category talk:Units of velocity

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Hello, shall we rename this category to "Units of speed"? Velocity is a vector quantity, and speed is the magnitude of velocity. Units are attached to the scalar quantity, speed. When a velocity is stated with some units, the units are attached to the magnitude in each direction (customarily unit basis vectors). I don't see that there's any precision that's gained by referring to "units of velocity" rather than "units of speed". Thoughts? Regards, Wile E. Heresiarch 16:01, 26 Jun 2004 (UTC)

I added 'units of speed' and 'units of velocity' to the category's description to cover the use of the units in either case. I agree with your statement that velocity is speed with direction. The physical dimensions of both are L/T (Speed uses L=distance; Velocity uses L=displacement, where displacement is a vector analog of the scalar 'distance'. I think it's valid to speak of a speed of 5 m/s or a velocity of 5 m/s northwards. Either way, the dimensional units are m/s. Would it help to adjust the description to mention vector vs scalar? Icairns 00:45, 27 Jun 2004 (UTC)

Well, here's another way to look at it. When something is described in terms of meters per second, it doesn't say anything about direction. So meters per second must not be a unit of velocity (since if it were, "X m/s" would indicate direction). Yes? Wile E. Heresiarch 00:15, 28 Jun 2004 (UTC)

What are your units of velocity - unit vectors? Given that there are no 'golden axes' in the Universe, indicating fixed reference directions, then will you need to specify the reference frame directions included in your unit vector definitions? On another tack, using Google, I can find university references which agree L/T and m/s for Velocity, e.g.

[1] as well as the SI webpage [2] ian cairns 00:28, 28 Jun 2004 (UTC)

I agree that given the articles within this category, it should say 'speed' rather than 'velocity'. Bobblewik  (talk) 17:32, 15 Sep 2004 (UTC)