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joule and newton[edit]

The following quote is confusion joule and newton. I'll delete it. "One joule is also: The work required to accelerate one kilogram at a rate of 1 m·s-2 " Bo Jacoby 09:05, 24 March 2006 (UTC)Reply[reply]

No, it's not. It's the work required to accelerate one kilogram to a speed of m·s-1, regardless of the rate of acceleration. One kilogram that is accelerated at a rate of 1 m·s-2 corresponds to a force of one newton. --Shastra 16:57, 20 August 2006 (UTC)Reply[reply]
Please type a few words explaining why a speed of a meter per second is no longer written as 1m/s but is written using "a meter TIMES a second to the power of (0-1)" which, if people lack the tools to make superscripts indicating that "-1" is an exponent, looks like "second minus one". But aside from that, most people simply have a very direct understanding of speed as "a rate of travel such that if it were continued for a specified amount of time, then a calculable distance would have been traveled", and of acceleration or deceleration as "a rate of change in speed such that if that rate of change in speed were continued for a specified amount of time, then a calculable change in speed will have occurred" without bending their heads around the idea of seconds raised to negative powers. Or even positive powers. Anyone can instantly "get" that Area is going to be some form of Distance raised to the second power, and that Distance is going to be the square root of Area. You can SEE it as a picture, and it's not dependent on defining any units. An "Area", regardless of what units it's expressed in, is some "Distance" (again, regardless of units), squared. Take for example the fact that the distance "3 feet" squared is "1 square yard". It's not a statement that, somehow, 3 squared is 1. It's about the QUANTITIES being measured, not the numbers of the units that that measure the quantity. The CONCEPT of area (as in what a sheet of paper has) is as taking WHATEVER it is that the CONCEPT of "Distance" (as in what a thread has) measures, and squaring it, which means not just squaring some real numbers that count the units, but squaring the actual things counted by those units. It's less clear what "a second squared" might be, and it's MY belief that it's just algebraic, that there really isn't any such thing as a second squared, but, rather, that "a second" is appearing twice in a calculation. For instance, you can use algebra to make it seem like the unit of acceleration is a meter divided by this thing that is a squared second. I don't see it that way. I see an acceleration as being a change in speed (with speed being expressed as a rate of meters per second as we all know it) that is accomplished at a rate such that the change in speed would be some definite amount if that rate of change endured for not less and not more than one second. So that is "(change in speed of so many units)/second", where the "units" in "so many units" is "meters per second" or "meters/second". This can be MANIPULATED to make it seem like dividing by "square seconds" is being talked about, but is it? We all have s SENSORY experience of what "a second" and what "per second" is like. What is the sensory experience of a second squared that is as easy for us to grasp as our sensory experience of a square (or cubed) meter?) 2600:1700:6759:B000:1C64:8308:33BC:E2D6 (talk) 04:10, 31 August 2023 (UTC)Christopher Lawrence SimpsonReply[reply]

=not sure what to do with this - should this be deleted?

the energy required to lift a small apple 10 centimetres (1/10 metre) by converting the heat that the quiet person produced, on a hundredth of second, in work, with 10% efficiency.

Yes, please remove it or change it. I don't know exactly how our muscles convert food into mechanical energy, but when it happens we use up more food energy than the basic 100 joules of "idling" energy that is converted to heat. So the calculation would be different. I think a more understandable example would be something like "one joule is the energy expended while walking 5 millimeters" (if that number is correct). --Shastra 17:47, 20 August 2006 (UTC)Reply[reply]


Somebody should put the pronounciation at the begining of the article.

It's pronounced "joole", but not eveybody knows that (I didn't for quite an while actually).

I would put it myself, but I don't know how to write with those fancy phonetic letters. Nor would I know which ones to use.

You know what... I am gonna just write "(pronounced 'joole')" and one of you guys fix that later. —The preceding unsigned comment was added by (talk) 09:37, 29 January 2007 (UTC).Reply[reply]

Good point, thanks for the contribution. I've updated it to the standard IPA definition. Slightly uncomfortable about the multiple parentheses making it difficult to parse the first sentence, but think it is probably okay. --LightYear 01:36, 30 January 2007 (UTC)Reply[reply]

Maybe a silly question, but why French pronunciation when James Prescott Joule was an Englishman? --Kompik 17:51, 31 January 2007 (UTC)Reply[reply]

Seems like a good question to me, but I'm in no position to give you an answer. I do have a counter question for you though - how would it be pronounced by an Englishman? --LightYear 02:46, 1 February 2007 (UTC)Reply[reply]

I've tried Google search [1]. Merriam-Webster mentions both pronunciations: dzu:l and dzaul. First glance at the first results from this google search suggests that most dictionaries use the pronunciation dzu:l. Wikipedia article James Prescott Joule mentions

It seems that the pronunciation of the name Joule was not really standardized during the scientist's lifetime and that his family's brewery even used this confusion for a rhyming ad: Whatever you call it... it's GOOD!

--Kompik 11:26, 1 February 2007 (UTC)Reply[reply]

What?? I know that it is pronounced like DJOOL with the d in the beggining and no e on the end.--Simpaklimp (talk) 10:33, 28 March 2009 (UTC)Reply[reply]
I've almost always heard people say /l/, which is the pronunciation I've always used, and I've read that that's how James Prescott Joule probably pronounced his surname (though some members of his family may have said /l/), so I think said pronunciation is in all likelihood appropriate.--Solomonfromfinland (talk) 02:47, 18 July 2016 (UTC)Reply[reply]

A new pronunciation /l/ (before the old /l/) with two good but old references was just added to the top of the article. I have (working as a physicist) never heard this pronunciation and suspect that it is mainly historical. That seems to be backed by the Marriam-Webster [2] calling this pronunciation non-standard, giving the /l/ as the standard one. I would like the article to not include the /l/ pronunciation or refer to it as historical or non-standard. Any thoughts on this? Ulflund (talk) 01:57, 6 June 2019 (UTC)Reply[reply]

I am the one that added the "new" /l/ pronunciation. Like Ulflund says, it is backed by multiple good references. It is how the Joule unit is pronounced in parts of the world today, it's not just historical. Sure, this pronunciation is non-standard but how is that relevant if the earliest references suggest that that's how the man pronounced his own last name? Yonibaciu (talk) 14:01, 4 September 2019 (UTC)Reply[reply]

This article is not about the person, but about the unit. How he pronounced his name has little importance if that is not how the unit is pronounced today. Ulflund (talk) 05:08, 6 September 2019 (UTC)Reply[reply]
The reference I found from 1901 is about the pronunciation of the unit, not the man. And as I wrote before, it is still being pronounced "jawl" in many countries today. Yonibaciu (talk) 21:04, 7 October 2019 (UTC)Reply[reply]
The sources in the article make a good case for listing jool first. Sources from 1900 have little bearing on current pronunciation. SI units often have significantly different pronunciations in various languages; a pronunciation similar to jawl in non-English languages has little relevance to this article, which is in the English language. I am requesting a third opinion. Jc3s5h (talk) 12:41, 16 June 2022 (UTC)Reply[reply]

JOWL / JAWL should be considered the primary pronunciation because that's how it was originally pronounced at least in 1901 (see reference at A new English dictionary on historical principles. The Clarendon press. January 1901. p. 606.) If someone finds an example earlier than 1901 for JOOL then, by all means, reverse the pronunciations order. Till then, please leave the correct one in place - JOWL then JOOL. — Preceding unsigned comment added by Yonibaciu (talkcontribs) 12:39, 16 June 2022 (UTC)Reply[reply]

Language is not constant, it changes over time - that's why American dictionaries say that the pronunciation of Worcester is /wʊstɚ/ and not /ˈwɔɹˌsɛstɚ/. Why should a 1901 pronunciation of a name take precedence over the modern pronunciation that nearly every dialect of English uses?
Additionally, how Joule pronounced his name isn't an authoritative source on the modern pronunciation of the unit. English speakers say /ˈaɪnstaɪn/, not /ˈaɪnʃtaɪn/. (talk) 05:23, 23 August 2022 (UTC)Reply[reply]

About the Third Opinion request: The request made at Third Opinion has been removed (i.e. declined). Like all other moderated content dispute resolution venues at Wikipedia, Third Opinion requires thorough recent talk page discussion before seeking assistance. If an editor will not discuss, consider the recommendations which are made here. — TransporterMan (TALK) 18:35, 16 June 2022 (UTC)Reply[reply]

Going through the sources for the pronunciation:

  • A new English dictionary on historical principles is early, and gives the JOWL pronunciation. But the issue is how is it pronounced today in the English language.
  • Prescott's letter to the editor of Nature in 1943 reviews various printed works with conflicting positions about the pronunciation. He then describes first, second, and third-hand statements from people who should know, including Lord Kelvin and members of the Joole family that the pronciation was JOOL.
  • I don't have the source by Wells, but another reputable source affiliated with Oxford University Press is Lexico. For both James Prescott Joule and the unit of energy, in either US or UK English, it give the JOOL pronunciation. Jc3s5h (talk) 19:00, 16 June 2022 (UTC)Reply[reply]
I agree that the important issue is how it is pronounced today in the English language (in all of its dialects). I'm also not sure how "this pronunciation is non-standard" is compatible with "it should be considered the primary pronunciation".
WP:Pronunciation suggests that a "possibility is to relegate everything beyond the most common pronunciation to a footnote", and I think that may make sense here. IpseCustos (talk) 19:26, 16 June 2022 (UTC)Reply[reply]

What we have right now is a section with a single sentence stating '"Joule" is pronounced as /ˈl/ JOOL' with multiple references to back this up. I think it makes the best sense to put this info in the lead sentence without the refrernces and not discuss the matter further within the article itself. We do not need to cite that the sky is blue, and all modern physicists pronounce it "jool", end of discussion. The only reason we need the IPA at all is to firmly reject the alternate incorrect case of "jowl". Not that "jowl" has never been said or never used, only that it is currently not ever used for this unit of measurement. A loose necktie (talk) 23:14, 10 July 2023 (UTC)Reply[reply]

I have most often heard JOOL myself, but there is at least one modern physicist who pronounces it as JOWL (from March 2022). He even adds in a fun little poem making fun of the other pronunciation: "The fools who use JOOLs always scowl when I report my findings in JOWLs." He also cites Linus Pauling's General Chemistry textbook. Although I prefer the JOOL pronunciation, I don't think it's true that JOWL has fallen out of use, even in the U.S., let alone the rest of the world. Jdaniels8 (talk) 19:08, 23 September 2023 (UTC)Reply[reply]

Is the description missing something?[edit]

The description says "a force of one newton moving an object one meter along the direction of the force". Shouldn't that be "a force of one newton moving a one-kilogram object one meter along the direction of the force"? --Musanim 16:43, 3 June 2007 (UTC)Reply[reply]

No. The newton already takes care of the weight of the object. It could be a 100kg object being pushed on non-ideal rollers, or a 0.1kg object being pushed vertically, as long as the resulting force is 1 newton. LightYear 03:03, 4 June 2007 (UTC)Reply[reply]
That might be a good explanation, but if it is, it should be in the article, not back here on the talk pages.2600:1700:6759:B000:1C64:8308:33BC:E2D6 (talk) 05:26, 31 August 2023 (UTC)Christopher Lawrence SimpsonReply[reply]
I'm not getting something here. What if a force of 1 newton were applied to an object with very little mass; wouldn't it just accelerate more quickly than a more massive object (and traverse 1 meter in much less time)?--Musanim 01:35, 5 June 2007 (UTC)Reply[reply]
Indeed, one newton applied to a very light object will have that object moving at a terrific (change of) pace by the end of the metre. The kinetic energy (0.5mv^2) gained by the object (1J) during the event will still be the same as that of a slower moving, heavy object (which underwent the same 1N force along a metre). Joule is a measure of energy, not velocity or power (both of which involve time, as you are expecting). There's probably a better forum for this - study some physics sources, and the initiallly counter-intuitive concept will click for you. LightYear 05:21, 5 June 2007 (UTC)Reply[reply]
The newton unit already takes into account the mass of the object. F = ma, and 1 newton == 1 kilogram * 1 m/s^2. So a given force, say one newton, can accelerate a large object slowly, or a small object quickly. Foobaz·o< 06:01, 6 June 2007 (UTC)Reply[reply]
After thinking about this for a while, I finally got it. At first, it seemed that a 1 kilogram object being pushed with a 1 newton force for 1.414 seconds to move it a meter had to involve more work than a 1 gram object being pushed with a 1 newton force for 0.0447 seconds to move it a meter. But then I considered what might apply such a force, and I imagined a second object being acted on by gravity (pulling at right angles to the first object, through a pulley). Since the second weight falls the same distance in both cases, the same work is done. QED. Thanks for your help.--Musanim 01:30, 8 June 2007 (UTC)Reply[reply]
I think you're still making an error. A Force doesn't "move" an object. It accelerates it (or decelerates it if the object was already moving before the Force was applied to it). After the application of the Force is gone, the object is still moving, isn't it? (I'm thinking of a ball floating in outer space that has been hit by another ball.) Your aim in applying a Force to a mass isn't to move the mass to another place. It's to change the speed at which the mass is moving to another place (or GIVE it a speed, if the object started out with no speed at all). A Force doesn't change where an object is. It changes how fast it's going. If the object is already moving, then if there's no Force at all, the object still moves.2600:1700:6759:B000:1C64:8308:33BC:E2D6 (talk) 05:26, 31 August 2023 (UTC)Christopher Lawrence SimpsonReply[reply]

The lede is actually misleading in talking about moving a mass or object at all. It is a 1 N force acting over 1 meter, simple as that. Doesn't matter what the force is pushing on. It doesn't need to move a mass, maybe we are stretching a spring or something. — Preceding unsigned comment added by 2001:480:91:FF00:0:0:0:15 (talk) 18:51, 24 May 2022 (UTC)Reply[reply]

I'm not sure that I would consider it misleading so much as illustrative. We give the definition of a calorie as the amount of energy it takes to heat a gram of water by one degree, but the energy can be used in other ways too. (talk) 22:49, 18 September 2022 (UTC)Reply[reply]

Wrong description[edit]

Euuu ... isn't the start of this page ENTIRELY wrong ? Take 1 vacuum, take no fiction, once i get the mass going, it will move indefinite ... What COULD be correct is that 1 Joule is the force required to accelerate 1KG to 1m per second. THAT makes sense... If you don't believe me, i recommend looking it up on GOOD scientific source. Or use the SI definition, clearly states kg * m2 / s2 AKA: acceleration of 1 kg to 1 meter per second. —Preceding unsigned comment added by (talk)

I agree that maybe there is a problem. The Comment above wasn't dated, and if it's old then the article might have been changed since the comment above, but as of the date/time of THIS comment that I'm typing, the article contains the sentence
It is equal to the amount of work done when a force of 1 newton displaces a mass through a distance of 1 metre in the direction of the force applied.
Is there an omission there? Should it say "It is equal to the amount of work done when a force of 1 newton displaces a mass OF ONE KILOGRAM" [emphasis mine] "through a distance of 1 metre in the direction of the force applied."? So, what the article says now is that if the mass being displaced is the Moon then the amount of work done is the same as if the mass being displaced is a golf-ball? Is that correct? If it's NOT correct please fix it. If it IS correct then edit the article to explain why the mass of the object is irrelevant to the idea of what a Joule is.
Further down, in the table under the subsection title "Definition", the article defines a Joule as being equal to language that amounts to "a kg multiplied by a square meter divided by a square second", i.e. something that causes a specified mass (in this case, 1 kilogram) to undergo a specified acceleration (in this case, a rate of increase in speed such that during a second the speed would increase by 1 meter per second) over a distance of 1 meter. The "1 kilogram of mass" in this definition seems to me to contradict the sentence about which I have some concerns, as that sentence seems to me to imply that the mass could be ANY MASS, not restricted to a mass of one kilogram.
I am no longer sure that the QUOTED sentence above errs in its omission of a kilogram being the mass moved. It might, rather, have something to do with the verb "displaces". A Force dos not displace an object. It imparts an acceleration to it. If the Force continues for awhile and then goes away, the object continues to move, i.e. it continues to be FURTHER displaced from where it started before the Force arrived (I'm imagining a ball floating in outer space) even though the Force is gone. I can imagine that a Force can be applied to an object during the time it takes for the object to respond to the Force by moving one meter (stated in other sources to be "applied over the course of one meter" rather than "displaced through one meter"), and that the Force can be removed after the meter has been traveled, but I am really uncertain that it's correct to speak of a Force as "displacing" an object instead of imparting to the object its own tendency to keep on racking up additional "displacement" after the Force is gone.2600:1700:6759:B000:1C64:8308:33BC:E2D6 (talk) 04:10, 31 August 2023 (UTC)Christopher Lawrence Simpson2600:1700:6759:B000:1C64:8308:33BC:E2D6 (talk) 05:51, 31 August 2023 (UTC)Christopher Lawrence SimpsonReply[reply]
See discussion titled "#Joule needs specific units for definition." below. Jähmefyysikko (talk) 04:23, 31 August 2023 (UTC)Reply[reply]

Joule needs specific units for definition.[edit]

Joule is a specific unit of measurement. But the definition here includes a non specific amount of mass. Either remove quantifications for force and distance or provide a specific quantification also for mass.

"It is equal to the amount of work done when a force of 1 newton displaces a mass through a distance of 1 metre in the direction of the force applied."

The definition of a unit must be consistent. If mass is left unspecified then the amount of work 1 joule represents is not consistent.

Consider the SI base units: kg*m^2/s^2

All base units require a quantity.,2%E2%8B%85s%E2%88%922).

To define a single unit of 1 joule requires the quantification of mass as well as disrance and time.

Darghil (talk) 13:28, 1 August 2023 (UTC)Reply[reply]

In terms of base units, J = kg m2 s−2 and in terms of other SI units, J = N m. The newton N = kg m s-2; note the kg, and the definition quoted in SI Brochure 9 ratified at the 1948 CGPM, "The joule is the work done when the point of application of 1 MKS unit of force [newton] moves a distance of 1 metre in the direction of the force" or the source you linked above, "Alternatively, it is the amount of work done on an object when a force of one newton acts in the direction of the object's motion over a distance of one meter (1 joule equal 1 newton meter or N⋅m)." NebY (talk) 13:42, 1 August 2023 (UTC)Reply[reply]
The Newton is defined using 1 kilogram.
If you wish to substitute you must do it fully.
To leave mass unspecified in the definition of a joule is nonsense. Darghil (talk) 14:04, 1 August 2023 (UTC)Reply[reply]
Quote the exact words in the article that you object to. Jc3s5h (talk) 14:12, 1 August 2023 (UTC)Reply[reply]
It seems User:Darghil assumes that "mass" must be defined in our current
It is equal to the amount of work done when a force of 1 newton displaces a mass through a distance of 1 metre in the direction of the force applied.
The CGPM resolution used "point of application" and their (non-RS) source above uses "object". Perhaps we could usefully substititute "object" for "mass", giving
It is equal to the amount of work done when a force of 1 newton displaces an object through a distance of 1 metre in the direction of the force applied.
NebY (talk) 14:34, 1 August 2023 (UTC)Reply[reply]
Agreed, 'object' would be better, since we are not referring to the property of the object (inertial mass) but the object itself. Jähmefyysikko (talk) 14:44, 1 August 2023 (UTC)Reply[reply]
a few references
Units of energy Darghil (talk) 14:55, 1 August 2023 (UTC)Reply[reply]
it's impossible to define a joule using base units without specifiers or to define it by specifying a few and leaving any one base unit as arbitrary.
"Object" is not only arbitrary its not part of any definition you'll find anywhere.
Actually the definition you're defending requires a reference. It's unique and errant. Darghil (talk) 15:00, 1 August 2023 (UTC)Reply[reply]
We are defining joule with newton. The definition of newton includes a reference to kilogram, so we do not need to include it here. Jähmefyysikko (talk) 15:05, 1 August 2023 (UTC)Reply[reply]
from Wikipedia a newton is "defined as 1 kg⋅m/s2, the force which gives a mass of 1 kilogram an acceleration of 1 metre per second per second". Darghil (talk) 15:09, 1 August 2023 (UTC)Reply[reply]
In your opinion, should we also state that the displacement of 1 meter has to happen in 1 second? Jähmefyysikko (talk) 15:22, 1 August 2023 (UTC)Reply[reply]
You say '"Object" is not only arbitrary its not part of any definition you'll find anywhere.' This is not true. Above, you cited,2%E2%8B%85s%E2%88%922). That states
"Alternatively, it is the amount of work done on an object when a force of one newton acts in the direction of the object's motion over a distance of one meter (1 joule equal 1 newton meter or N⋅m)."
NebY (talk) 15:26, 1 August 2023 (UTC)Reply[reply]
I would revert to using the word mass rather than object. The definition of joule using the word "mass" is more general, without the need for an additional definition of object, which is ambiguous. (of course as others have said there is no need to specify that the mass is 1 kg) --Ita140188 (talk) 15:45, 1 August 2023 (UTC)Reply[reply]
The sentence that seems to be in question is in the lead of the article, and states

It is equal to the amount of work done when a force of 1 newton displaces an object through a distance of 1 metre in the direction of the force applied.

The sentence does not say this is the definition, it just says "is equal". It goes on to give another scenario that dissipates one joule of energy. Later in the article there is a "Definition" section. Any quibbling over what counts as a definition versus one of many scenarios that involves an energy of one joule should be discussed on this talk page and should concentrate on what, if any, changes are needed to the "Definition" section.
Once could quibble about whether the words "is equal to the amount of work done". Trying to find a phrase that is accurate but not so esoteric that a general reader looking at the lead won't understand it not easy. "A joule is dissipated" may not be accurate; the energy may be stored as potential energy. But then again, the energy is dissipated in some scenarios. Equality is a mathematical concept, deciding if a scenario is equal to a unit of measure really isn't a mathematical operation. Jc3s5h (talk) 16:22, 1 August 2023 (UTC)Reply[reply]
(edit conflict)The old CGPM definition (above) has "point of application", which various dictionaries and handbooks copy; our second citation[1] has "when a force of one newton acts through a distance of one meter" and others are similar; "object" is rarer but does occur[3][4] and I think is more easily apprehended than "point of application". I haven't yet found another use of "mass" and I fear it may be a trap for the unwary. NebY (talk) 16:31, 1 August 2023 (UTC)Reply[reply]


  1. ^ American Heritage Dictionary of the English Language, Online Edition (2009). Houghton Mifflin Co., hosted by Yahoo! Education.