Talk:Conversion of units/Archive 2008

Mass

Why is there a whole column in the Mass table labeled "Relation to avoirdupois units" when there is nothing in that column? Is someone in the middle of working on putting information in there? Yoshi thomas (talk) 15:30, 9 February 2008 (UTC)

I don't know why it is there, but I think it would be good to fill in the table selectively; after all, this article is about conversion. If you know how, go ahead. It would be great if you could provide sources for what you add, especially if it's unusual. --Gerry Ashton (talk) 19:40, 9 February 2008 (UTC)

Time - Micro-Fortnight

I first heard the term micro-fortnight used in the early 1990's, it's approximately 20 minutes (actually 1,209.6s) and defined as 2 wk / 1000.

Is it a time unit with any meaning, and if so should it be included, or is / was it just a geeky way of saying 20 minutes? DMcMPO11AAUK/Talk/Contribs 11:17, 3 March 2008 (UTC)

What you describe is actually a millifortnight. In any event, I think it's only a geeky joke. Probably doesn't belong in this article. -- BPMullins | Talk 14:32, 3 March 2008 (UTC)

horsepower (European electrical)

I am somewhat confused by this unit. It seems to me that horsepower(European electrical) is the same as horsepower(metric). The only difference is the definition contains kilopond instead of kgf. I any event, using the definition I come up with 735.49875 watts. Would someone be able to look at this and comment on this unit? --Richard Wolfgram 01:51, 8 March 2008 (UTC)

French catheter scale

If no one minds, I'll add the French catheter scale to length units. This unit is widely used in the medical field. It can be referenced in Wikipedia at French_catheter_scale --Richard Wolfgram 02:06, 8 March 2008 (UTC)

I removed the French catheter scale. I appears that the article in Wikipedia may be incorrect. After reviewing some doctors comments the correct conversion appears to be 1 FR = 1/π mm. When I get a definitive answer I'll add it back in. Rpwolfgram (talk) 19:11, 8 March 2008 (UTC)

I am adding French Gauge back in. According to the International Committee of the Red Cross 1 FR = 1/3 mm. Not to mention that all scale tables on the internet show this to be the case. I hope someone will clean up the Wikipedia article and show the equation accurately --Rpwolfgram (talk) 20:43, 8 March 2008 (UTC)

Someone removed the synonym charriere. Why? The reference for this is from [icrc.org] and [Online Medical Dictionary] --Rpwolfgram (talk) 00:03, 9 March 2008 (UTC)

I restored a version that used an overbar to show a repeating decimal, rather than parentheses. I didn't notice the synonym when I did the restore. By the way, as far as I know, the use of parentheses to indicate repeating decimals is not taught in the USA, and will be unfamiliar to many readers. --Gerry Ashton (talk) 00:36, 9 March 2008 (UTC)

Blood glucose

Is this table linear? What is the source for this table? --Gerry Ashton (talk) 13:05, 24 March 2008 (UTC)

Seems to be an exhaustive list of individual conversions, rather than a single conversion factor like the other entries. It's like a table that says

• 1 ft = 12 in
• 2 ft = 24 in
• etc.

I deleted it for now. —johndburger 15:54, 24 March 2008 (UTC)

Corrections in Mass section

A large number of small measures in the mass section had lost the minus sign on the exponent, which made for some nonsensical definitions.

I've tried to fix them, but please check my work. There are things there I've never even heard of. -- BPMullins | Talk 05:34, 1 May 2008 (UTC)

Single unit tables?

Do we really want to have tables that only contain one entry, as with Inductance? --Gerry Ashton (talk) 20:27, 1 June 2008 (UTC)

It looks like a useful bit of content, allowing H to be converted to other combinations of units. Dicklyon (talk) 20:30, 1 June 2008 (UTC)

I see the value of stating equivalent combinations of SI units that are equivalent to a henry, but isn't the Henry (unit) article sufficient? I can't imagine any desire to convert to or from any other inductance unit, unless one is working with papers from the 19th or early 20th century. --Gerry Ashton (talk) 20:36, 1 June 2008 (UTC)

Sure the Henry article is probably "sufficient"; most of the other conversions are probably also covered in articles on the respective units and concepts. That shouldn't rule out having it here in this collection, too. And if someone is working on stuff with old units, it will good to have handy; maybe they'll even add some old units. Dicklyon (talk) 20:47, 1 June 2008 (UTC)

WARNING - Correct this page

Although there is a suprising amount of work gone into this page, there is some problems with the accuracy of it, particullary with standard form or indicies. For example the cubic meter to the cubic inch is 1.63871(10^-5) not to the -6. —Preceding unsigned comment added by 81.79.180.109 (talk • contribs)

See section at bottom of page: #Massive errors inserted April 22-27 2008. Dicklyon (talk) 01:32, 28 June 2008 (UTC)

Grams?

I was looking at this page, and I'm just curious, why are grams not noted anywhere on this page? This would be the page I would think that they would be on, but they're not. —Preceding unsigned comment added by 76.174.205.123 (talk) 06:25, 8 July 2008 (UTC)

Conversions between units with the same root but different prefixes (say, milligram to kilogram) are not mentioned in this article to keep it to a manageable size. The base unit of mass in SI is the kilogram, not the gram. This is because it is part of a coherent set of units. To learn about the advantages of coherent units, see the back cover of Guide for the Use of the International System of Units (SI). --Gerry Ashton (talk) 13:50, 8 July 2008 (UTC)

It seems to me that since kg is the base unit, but gram is also an important unit, that it would be worthy of an exception to the usual practice of not including conversions based on just prefix differences, maybe with a special note about why it's included. Dicklyon (talk) 20:46, 8 July 2008 (UTC)

Many Volume SIs incorrect by factor of 10

The SI values for all of the volumes listed from "drop (metric)" through "pint (U.S. fluid)" except "drop (medical)" and "cubic inch" are low by a factor of 10. Amazingly, even "drop (metric)", defined as 1/20mL, is listed as "5 ×10−9 m³". Values for volumes greater than a pint seem OK (to an order of magnitude anyway). I'm a neophyte at this, but I'll check back on this tomorrow and if no one has fixed it and no one objects I'll edit the SI's to appropriate values (10x higher). MacMcF (talk) 16:24, 30 July 2008 (UTC)

See the "Massive errors" talk section above. If you can adopt and fix this section, that will be good progess. Dicklyon (talk) 06:42, 23 August 2008 (UTC)

Oh, I see you did. Thanks. Dicklyon (talk) 06:43, 23 August 2008 (UTC)

does anyone know the standard unit of pressure? —Preceding unsigned comment added by 70.180.136.33 (talk) 00:35, 27 August 2008 (UTC)

people do.

Massive errors inserted April 22-27 2008

An anon went through and changed a bunch of things during these days, which is why we're seeing so many exponent corrections needed now. I checked a few, and concluded that it's hit and miss, but heavy on the miss. All the pressures are screwed up, and are some of the conversions of liters to cubic meters that I noticed (like 250 mL going to 25 e-6 m^3).

How can we deal with this, other than reverting to before April 22? Dicklyon (talk) 05:03, 10 June 2008 (UTC)

I've going through in order from the first one; the first thing I might quibble about is the change of volume equivalents for gallons and such from liters to cubic meters; seems like it would be more useful to list both; but the numbers look OK and it's consistent with how things are being done here, except for not using exponents where they would useful. The first screwup is too many zeros in converting mm to m. Instead of someone fixing the whole thing, bits and pieces got noticed and fixed; for example "nail (cloth)" is still wrong; I haven't checked all carefully yet. Next, This one gets point wrong in four places, but those have been fixed. this one and the next screwed up the degree two different ways, making it clear that this editor is not good with his powers of ten. Then he messed up grad , minute of arc (three different wrong ways), etc. These three remain incorrect since April. After a run of good edits, he then gets into a run of wrong sign on exponents. Enough for now; can I get a volunteer to help go through these with me to check and correct sections that he messed up? I'll idesntify more in his subsequent edits. Dicklyon (talk) 15:58, 27 June 2008 (UTC)

I'll put a disputed tag on it until we find and fix all these order-of-magnitude errors. Dicklyon (talk) 01:29, 28 June 2008 (UTC)

Here in pressure or mechanical stress is the first one I had worked on; maybe not all fixed yet. Here's a massive blunder, still not fixed, off by 12 orders of magnitude. This one is just inconsistent with the rest. Then a string of edits speaks volumes about his uncertainty, as he got it wrong, then right, then wrong again. One really has to wonder what he was thiking here, just when you thought he had got some right; here and here and here, too. And then for a new record, one off by 18 orders of magnitude here, but he fixed it, then got back to this and a string of more mL errors. Then he squanders our time, tanks our velocity, and finally he made a luminance section, but at least someone looked at that. Did he fix it correctly? Don't know, haven't checked. Dicklyon (talk) 02:16, 28 June 2008 (UTC)

All fixed. Dicklyon (talk) 03:41, 28 September 2008 (UTC)

Pressure

The exponents for conversion from inches and feet of water and mercury to Pascals were listed as -3, when all should be 3. ---- DonWa777 —Preceding unsigned comment added by 136.181.195.84 (talk) 17:12, 9 July 2008 (UTC)

Thanks; that follows the topic two sections up; can you take on that section, and remove the disputed tag when you're pretty sure it's all fixed? Dicklyon (talk) 20:29, 9 July 2008 (UTC)

All done. Dicklyon (talk) 03:41, 28 September 2008 (UTC)

Volume SIs Corrected

I have corrected the order-of-magnitude errors noted above, and also converted these data into a consistent format. Previously, there was no consistency. For better or worse, I expressed all of the SI equivalents in engineering notation (exponents of 10³ⁿ) with leading non-zero. This may not appeal to some, but at least it's consistent, and if some other convention prevails it should be easy to convert the values to that convention. MacMcF (talk) 02:26, 1 August 2008 (UTC)

If you've checked the whole section, can you remove the disputed tag? If not, leave it. Dicklyon (talk) 06:45, 23 August 2008 (UTC)

All done. Dicklyon (talk) 03:41, 28 September 2008 (UTC)

Lengths reviewed

I have reviewed the Lengths table. I added references for many units, removed a few unreferenced ones that disagreed with references, and adjusted a few to make the value agree with a reference. I removed the "disputed" tag. --Gerry Ashton (talk) 22:37, 1 September 2008 (UTC)

Thanks, Gerry. I wish there were more like you willing to help. Dicklyon (talk) 04:06, 11 September 2008 (UTC)

All done. Dicklyon (talk) 03:41, 28 September 2008 (UTC)

Sections still to be fixed

Given the relatively little help being offered to check or fix the disputed sections, I intend to take them back to their pre-mangled (April 22 2008) states, so at least they'll be somewhat more right. Some improvements may be lost, but we'll be able to look at the diffs for each section that I put back and see if there are things we want. Dicklyon (talk) 03:06, 11 September 2008 (UTC)

OK, I took volume back, but on inspecting the diff found no errors; so I put it back and removed the disputed tag, as it looks fixed.

Then, I took angle back to pre April 22 with this diff. It's obvious that most of the values were wrong from April through now, so this fixes them. One could go through and correct individual numbers if the other style if preferred. Any takers? Dicklyon (talk) 03:50, 11 September 2008 (UTC)

Then mass, this diff; looks like only gamma was wrong, so it should be easy to take back to previous style and fix that if desired. Dicklyon (talk) 03:57, 11 September 2008 (UTC)

In time, this diff fixes svedberg and shake. Dicklyon (talk) 04:02, 11 September 2008 (UTC)

Have we got a consensus on style of the SI equivalents? Do we want to use engineering exponential notation? or SI prefixes? It was in converting from the latter to the former that all these errors were inserted. Let's decide which way we want it. For now, enough section reverts until we see how we handle these. Dicklyon (talk) 04:04, 11 September 2008 (UTC)

I'm not offering an opinion on the best format right now, except I wouldn't use exponential notation if the decimal point falls somewhere within the significant digits (excluding repeating decimals, of course).

I'm checking over the speed section, and so far have confirmed (but not touched the format) for everything but knot (Admiralty), speed of sound, and mach. --Gerry Ashton (talk) 04:39, 11 September 2008 (UTC)

Looks like it's all fixed now. Thanks for helping. Some sections may still need conversion to "scientific notation" instead of prefix notation, but I think the numbers are right (or least not differing by powers of 10 from what we had before April 22). Dicklyon (talk) 03:41, 28 September 2008 (UTC)

Torque

We've got to get around to including torque ... as a seperate table rather than pretending that torque and energy are equivalent. Jɪmp 03:15, 26 March 2008 (UTC) Okay, I've made a start. Jɪmp 03:27, 26 March 2008 (UTC)

what????? —Preceding unsigned comment added by Donmags07 (talk • contribs) 03:04, 4 November 2008 (UTC)

One entry tables?

Should we have tables that list only one unit, like the inductance table? If no conversion factors are being provided, does it really belong in this article? --Gerry Ashton (talk) 20:54, 8 November 2008 (UTC)