Talk:List of physical quantities
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Wrong dimension of Intensity
editThe dimension of Intensity is, as the unit W/m^2 suggests, L^2 M T^-3 / L^2 = M T^-3. Majortom777 (talk) 21:51, 6 June 2016 (UTC)
Symbol for velocity
editThe symbol for velocity is "v", not "V". UED77 22:21, 2004 Sep 12 (UTC)
Big change
editWhy not remove the SI-Units (since this is a list of physical quantities and not physical units) and use some more space on information regarding vector/scalar and intrinsic/extrinsic property, etc.?
- That's actually a good idea. Karol 15:43, 1 January 2006 (UTC)
- Agree, someone can make a new/improved table? Thechamelon 22:14, 2 January 2006 (UTC)
- I just did. Karol 02:47, 3 January 2006 (UTC)
- The SI units are WAY too related to the properties to move from here. Also, it'd be pretty ridiculous have a long table of just properties and their units. How useful would that be?
Seriously, just because a column heading isn't in the title of page does not mean it doesn't completely belong there. Besides, if readers really wanted to know more about the "Comments" stuff of a particular quantity, they could easily click the its link.--ArtifexCrastinus (talk) 07:27, 8 September 2008 (UTC)
Question
editQuestion: Doesn't velocity require a vector, while speed does not?
A legend of dimensions symbols would be nice
editIt would be nice to let the reader what [M], [L], [T],... stand for. Headbomb {ταλκ – WP Physics: PotW} 13:03, 25 July 2008 (UTC)
- Isn't that exactly what the first table does? (among other things.) (TimothyRias (talk) 14:19, 25 July 2008 (UTC))
- If that's what it's supposed to do, then there are some major inconsistencies. 1 would be given as the "symbol" for both plane and solid angles. Then index of refraction is listed as being of dimensions 1 (which is accurate, as it is of unit dimension), but if that table is meant to define the [L], [T], etc... then this is saying that index of refraction are given in units of plane/solid angles. Headbomb {ταλκ – WP Physics: PotW} 14:32, 25 July 2008 (UTC)
- Plane and solid angles are dimensionless quantities, and hence carry unit dimension 1, just like index of refraction. (TimothyRias (talk) 21:42, 25 July 2008 (UTC))
- The second table is units that are derived off the first table (Thus it's the "Base" table). If you wanted, you could use only the first table and be able to describe any quantity / unit (although that would be cumbersome, which is why we have the second table). MysticMetal (talk) 09:19, 21 September 2010 (UTC)
Where's specific gravity?
editI know it's dimensionless, but it should definitely be up here.--ArtifexCrastinus (talk) 07:31, 8 September 2008 (UTC)
- Well feel free to add it. As it is this list is mostly a compilation of the various BIPM tables with physical quantities. Undoubtedly, there are still many quantities missing from this list. (TimothyRias (talk) 08:12, 8 September 2008 (UTC))
Using Symbols
editShouldn't there be something in the introduction about using symbols in such places as custom equations and column headings. I've often seen them with subscripts to right of them indicating the substance of which they describe. For example, the mass of a lead object can be represented as mPb. Is this not as common as I thought? --ArtifexCrastinus (talk) 07:43, 8 September 2008 (UTC)
Current is not a base quantity
editCurrent is not a base quantity, charge (Coulombs) is. (Current is Charge / time). MysticMetal (talk) 09:19, 21 September 2010 (UTC)
Another sortable column
editShould we add a sortable column that says what it's generally used for (Chemistry, Electricity/magnetism, Physics), so if someone's interested in Electrical properties, they can sort based on that column (I came upon this page wondering about physical quantities...)? MysticMetal (talk) 09:22, 21 September 2010 (UTC)
- I think it would be impossible to unambiguously assign some quantities to one particular field.TimothyRias (talk) 09:33, 21 September 2010 (UTC)
Article organization
editShould we have it generally sorted so chemical properties are before (<) electrical < physical < magnetic? So far it's just cobbled together... --MysticMetal (talk) 09:27, 21 September 2010 (UTC)
merge proposal
editThe articles defining equation (physics) and defining equation (physical chemistry) are essentially the same with formulae, units, and dimensions in excruciating detail but they lack the 1-phrase explanation style given in this article. What do people think of splitting and transferring content from this article into those? Maschen (talk) 08:00, 5 September 2012 (UTC)
I would agree. Njaohnt (talk) 17:53, 3 November 2012 (UTC)
ISO/IEC 80000
editSince there is an international standard system of physical quantities (ISO/IEC 80000) why isn't this list page based on it? D.keenan (talk) 02:46, 11 May 2017 (UTC)
Plane Angle and Solid Angle on which table?
editPlane Angle and Solid Angle were previously listed in the Base Quantities list. But now they are in Derived quantities list. I think they should be listed in the Base Quantities list. Che12PM 13:51, 6 June 2017 (UTC)
- Yes plane and solid angle should be in the fundamental table. M∧Ŝc2ħεИτlk 15:55, 6 June 2017 (UTC)
- BIPM classifies rad and sr as derived units (see NIST SP 330, Table 3); I guess this is an argument that they should not appear in the base quantities table. If one considers them to be dimensionless, as they typically are, this makes sense, in the same way that the zero vector cannot be an element of a basis. (Even in my own quirky view, where angle should be treated as a dimensionful quantity, sr = rad2 would still be a derived unit). —Quondum 16:26, 20 June 2017 (UTC)
Isn't Information (i.e. bits and bytes) a Base Quantity?
editNIST (at [[1]]) considers bytes/MB/GB/etc. to be SI units; a whole special system of binary prefixes has been created by IEC.
So, is information / data storage measured in a base quantity, or as a population (like people or moles) based on the base quantity "amount"? Casu Marzu (talk) 19:58, 8 June 2017 (UTC)
- I don't see how you read that into the page you linked; it is talking about non-SI usage. SI is pretty clear: it defines seven base quantities, and information and data storage are not amongst them. Even though the edge cases may be debatable (the "dimensionless" angle, information/entropy, data storage capacity, and logarithmic quantities in general might be considered dimensionful, while amount of substance is apparently dimensionless, and luminance and temperature arguably are derived quantities), we do not have the scope on WP to argue against the standard and nearly universal approach. So, interesting as the debate might be, in this context, I think the answer is a pretty clear "no". —Quondum 17:09, 20 June 2017 (UTC)
Dimension
editAdding the simplest formula of the physical quantity will make the dimension essey. If you will aggery my suggestion ,it must be better for it. Padmanabha Dhala (talk) 05:00, 29 June 2019 (UTC)
GM/c2
edithow about explaining GM/c2 as a usual astrophysical unit (in the theory of black holes) including "G"? thanx! HilmarHansWerner (talk) 12:49, 17 February 2021 (UTC)
Electric Dipole Moment
editI would like to add electric dipole moment. ScientistBuilder (talk) 17:01, 24 January 2022 (UTC)ScientistBuilderScientistBuilder (talk) 17:01, 24 January 2022 (UTC)
- Consider it done. DWIII (talk) 22:35, 12 February 2022 (UTC)
Maths
editAbout physical quantities 196.189.182.87 (talk) 05:32, 12 May 2022 (UTC)