# Talk:Volume

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## Capacity

What sense does it make to say a solid block of steel has a big capacity of 20 liters? I do not now what any standards body has said on this yet, but it seems capacity should be for containers - the container itself occupying much LESS volume of space --JimWae 20:20, 2004 Dec 14 (UTC)

If it is a solid block, it has a capacity of zero. Make it a sheet enclosing something, as the passenger compartment in an automobile, or its trunk, and you can measure that capacity in volume units such as liters or cubic feet. The total space that would enclose both the container and its contents (the overall volume) is irrelevant to capacity. Gene Nygaard 21:32, 14 Dec 2004 (UTC)

So we are agreeing - but since the volume of a container can be taken to mean its capacity OR its water displacement, it would be clearer NOT to use volume & capacity as synonyms, but reserve capacity for how much containers can hold, and volume for displacement. --JimWae 21:40, 2004 Dec 14 (UTC)

Hey, do you prefer "useful volume" or "effective volume" when you mean the above "capacity"? Non-native speaker asking. Marine33sohu (talk) 01:42, 18 August 2011 (UTC)
I mean "how much a container can hold" - and it is not clear to me that your 2 alternatives are different --JimWae (talk) 01:57, 18 August 2011 (UTC)

## Litre

Resolved

Whether small 'l' or capital 'L'? Please let me know which one is appropriate "mL" or "ml" as abbriviation of mililiter.

## Stere

The symbol for the stere, the unit of volume for firewood, shall be “st” and not “s”, which had been previously assigned to it by the CIPM. (page 50 of SI brochure)--JimWae 20:28, 2004 Dec 14 (UTC)

The change occurred in 1948 (ninth CGPM). Urhixidur 13:56, 2005 May 26 (UTC)

## Ambiguity in defining volume function

In mathematics, there is presently some ambiguity in defining the volume function. I'm not qualified to write about this, but I am qualified to ask about it, so I'll ask anyone with a background in absolute geometry to lend a hand. (This ambiguity has significant impact on set theory.)

## What is the difference between m3/h and nm3/h?

We find air volume and liquid volume explained in m3/h and nm3/h. What is the difference between them?

Context would help in answering your question. The units of flow (not volume) cubic metre per hour (m³/h) and cubic nanometre per hour (nm³/h) differ by a whopping factor of 1027. If the second unit is actually cubic nautical miles per hour (NM³/h), the difference is a factor of 6×109 (6,352,182,208). Urhixidur 13:45, 2005 May 26 (UTC)

Nm3 is Normal meter cube : measured at 0 degree centigrade temperature and 1 atmosphere pressure. Since gas volume depends on both, you need to define the base for volume measurement, hence the N in nm3

## 4-d space

What is the volume of a 4-dimensional space, and can that be included?

I think that would be something completely different, as different as comparing length and area.
There's no common name for m4, ft4 etc. and that doesn't really matter in the real world since the idea's uncomprehensible. Maybe hypervolume. —The preceding unsigned comment was added by 74.72.95.145 (talkcontribs) 03:22, 16 September 2006 (UTC)
Mathematically there is no difficulty in defining the 4-D analogy to 3-D volume. I believe that to be outside the scope of this article, though. --Swift 05:27, 16 September 20050000(UTC)
Should it be outside the scope of this article? The generalized concept of "volume" to n dimensions may not belong here, but there doesn't seem to be an article where it's explicitly discussed. The closest things seem to be Lebesgue measure and volume form. Is that a problem? Rckrone (talk) 02:57, 25 July 2009 (UTC)
As someone said before, hypervolume is probably what you're looking for. On the other hand, if you mean the volume (as a quantity with unit m3) of a 4-dimensional space, it would be like the area of a 3-dimensional space. Since the surface of a 3-dimensional space is 2-dimensional (an area), the surface of a 4-dimensional space would be 3-dimensional, hence a volume. --Kri (talk) 09:14, 25 July 2009 (UTC)
No that's not what I mean. Length, area, volume, hypervolume, etc. are all instances of the same general concept, just in different numbers of dimensions. For lack of a better term, this generalized concept is often referred to simply as "volume" even when dealing with spaces or manifolds that don't have dimension 3. An example of this more generalized usage can be seen in the case of volume form. What I'm wondering is if this article shouldn't at least mention how the term "volume" can sometimes refer to this generalization, since it's something that people will encounter in math. For example, someone on the Lebesgue measure talk page was thrown off by this. Rckrone (talk) 05:49, 29 July 2009 (UTC)

## Gases

You can place objects in/through gases. —Preceding unsigned comment added by 99.224.229.97 (talk) 20:06, 23 April 2008 (UTC)
Yes, volume applies to anything with a conceivable boundary. --Swift (talk) 04:41, 13 February 2009 (UTC)

## Conversion Table

Needs a conversion table like the one in this page: http://en.wikipedia.org/wiki/Pressure. —Preceding unsigned comment added by 134.117.184.47 (talk) 15:08, 30 September 2007 (UTC)

Thanks for the suggestion. Pressure has specific units whereas volume is represented in terms of cubes of units of lengths. Volume conversion is done much like length conversion. --Swift (talk) 04:40, 13 February 2009 (UTC)

## Volume Formulae

Shouldn't the first few entries in the table be deleted, and instead replaced with the volume of any prism being the area of a cross section mutiplied by the height? It seems unnecessary to say that the area of any prism that has a constant cross sectional area along the height can be calculated by a times h, as ALL prisms have a constant cross section along its height. —Preceding unsigned comment added by 221.217.34.109 (talk) 11:55, 14 November 2008 (UTC)

On deleting the first entries: No, let's keep these for Wikipedia readers who aren't quite at the level of thinking about abstract formulas.
I've removed the mention of prisms' constant cross-sectional area. Thanks for the heads-up. --Swift (talk) 04:44, 13 February 2009 (UTC)

## Pluginless calculator

I have this page [1] which offers a handy calculator for any of the parameters of the volume equation. Do you agree to post it as an external link? I checked it and it complies with the external link guidelines. See you. Elpiades (talk) 05:13, 13 July 2009 (UTC)

Hi, MrOllie. Thanks for reviewing my contribution. You may agree with me that it's desirable to argument the reasons to edit other community member's contributions, and I'm really looking forward for you to do it. Please be aware that I made an insightful reading of the guidelines for external links and made myself sure that I didn't break them, instead of that I'm pretty sure that my contributions are helpful and free for anyone to use. Thanks again and good bye.
Elpiades (talk) 02:20, 17 July 2009 (UTC)

## Letter for the volume

What letter do one usually use for the volume? Is it capital V? I'm not sure, and this is not stated in the article. --Kri (talk) 10:41, 24 July 2009 (UTC)

## "Infinitesimal" surface slabs???

The article states:

"The volume of a sphere is the integral of infinitesimal circular slabs of thickness dx."

Oh, really? The idea of infinitesimals was how Newton and Leibniz explained calculus to themselves. At the time, Bishop Berkeley famously and accurately described infinitesimals as "the ghosts of departed quantities".

Infinitesimals were not put on a rigorous basis until more than 250 years later, and to do so requires some rather advanced mathematics. Without this quite advanced rigorous basis, the idea of infinitesimals is nonsense, and should not be inflicted on people who are just learning about these things.

A far better idea for this article is to describe the integral as the limit of certain sums (Riemann sums) that approximate the desired quantity (area, volume, etc.).Daqu (talk) 19:18, 23 November 2009 (UTC)

## Definition: substance v body

Putting "body" in the definition instead of "substance" strongly suggests a "solid substance". "Body" does not include mathematical shapes either - nor is it generally thought to include gases. Mathematical shapes do not occupy 3-D space, they are abstractions. We do speak of the "volume" of a shape, but this is abstract space. Anyway, "body" is just misleading & does not solve the "noun" issue as it does not include mathematical abstractions (except perhaps as a shorthand jargon within math circles). --JimWae (talk) 19:10, 1 May 2010 (UTC)

## Gill

The new image is from a 1914 book & includes gill, which is an almost entirely obsolete unit. It also gives an unbalanced view of what the most common units are, ignoring litres and spoons. Do we not want wikipedia to be a modern encyclopedia? --JimWae (talk) 22:35, 12 January 2011 (UTC)