[go: up one dir, main page]
More Web Proxy on the site http://driver.im/Jump to content

Talk:Energy

Page contents not supported in other languages.
From Wikipedia, the free encyclopedia


Lack of capitals at the start of sentences on the table

[edit]

The lack of capital letters at the start of each section of text in the table is bothering me, however I can't see how to edit said table as when I click on the pencil icon the text from the table is not displayed. Xboxsponge15 (talk) 15:49, 2 February 2022 (UTC)[reply]

It's transcluded from Template:Forms of energy. By the way, I don't think it was such a good idea to capitalise "joule" in the infobox. That's a sentence fragment, not a sentence, and it would be better to show the correct capitalisation for this unit name rather than correct sentence capitalisation. Compare Power (physics). It's actually abnormal to construct a sentence that starts with a unit name. SpinningSpark 16:14, 2 February 2022 (UTC)[reply]

any additional energy (of any form) acquired by an object will increase its mass

[edit]

"Due to mass–energy equivalence, any object that has mass when stationary (called rest mass) also has an equivalent amount of energy whose form is called rest energy, and any additional energy (of any form) acquired by the object above that rest energy will increase the object's total mass just as it increases its total energy."

Will a space ship increase in mass if it gains potential energy when raised from one circular orbit to a higher, slower circular orbit? Darsie42 (talk) 22:53, 6 April 2022 (UTC)[reply]

Most likely not! Its increased potential energy will be achieved by converting energy of some other form, so the total energy of the space ship might remain the same. Dolphin (t) 01:20, 7 April 2022 (UTC)[reply]
I believe that the energy would be considered to be stored in the gravitational field itself. In general relativity, spacetime has self-interaction. For example, it is possible to create a black hole from gravitational waves alone; the black hole would have mass and thus energy. However, I'm not sure if people really talk about it, since energy in GR is not well defined. I'm speaking as a layman on the topic so take what I say with a grain of salt. BirdValiant (talk) 01:32, 7 April 2022 (UTC)[reply]
No, Why should it? Even applying relativity considerations, if it is going slower, it will reduce in mass. Gpsanimator (talk) 00:31, 8 August 2024 (UTC)[reply]

This article's lede; expansion re light

[edit]

Spinningspark's recent edit summary asserts that "light is a form of energy," but it's more precise to say light, as we ordinarily encounter it, is a form of electromagnetic energy. A reminder: this article's header indicates the topic relates to scalar physical quantities, and the article itself details various subtopics including thermodynamic energy kinetic energy, potential energy, gravitational energy, elastic energy, chemical energy, but details little regarding "radiant energy carried by light". I'm ill-equipped to expand this article in a manner that cites descriptions of light beyond that vernacular given in this article (and in the Light article), but I'm personally undecided whether light is energy per se or whether light is an agent affected by gravitational energy and capable only of (a) refraction, (b) absorption, (c) both, or (d) neither in a hypothetical vacuum of space.

In a nutshell, the current lede is intended to provide three items – i.e., work, heat, and light – that exemplify readily comprehended types of energy, assuming light indeed is a form of energy, as is currently debated by mainstream physicists. Point of trivia: Cutting-edge quantum physicists have postulated that light is not energy per se but instead is capable of producing energy via quantum entanglement. Yet, once again, this article is about ordinary scalar physics, not the Theory of everything; so, describing light as energy seems fine within this article's ambit. --Kent Dominic·(talk) 15:33, 8 April 2022 (UTC)[reply]

Table, listing kinds of energy, falsely indicates that Sound Energy *doesn't* exist in solids!

[edit]

The speed of sound in steel, copper, etc, as Wikipedia articles explicitly-state, is *drastically* faster than it is in air, and both of those are crystalline-solids.

Please remove the "in fluid" term from the Sound energy row, correctly replacing that with "in matter", which IS correct

( pressure-waves propagate within our local star, so plasma can carry 'em, and if they can also travel through solid-crusts on neutron-stars, then they can travel through whatever the hell that stuff should be called, too!  : )

( : 66.171.48.141 (talk) 19:06, 12 May 2022 (UTC)[reply]

I've made the change. Wikipedia articles on sound don't clearly differentiate between "sound" as the term is used in physics and "sound" referring what and how ears hear. StarryGrandma (talk) 19:57, 13 May 2022 (UTC)[reply]

Semi-protected edit request on 22 May 2022

[edit]

Hi, I would like to propose an edit so it would make the concept of energy easier for people to understand. I believe this is an accurate description of energy, and it would help people understand physics better.

'In physics, energy is a quantitative property intrinsic to anything that is able to interact in the universe. The energy of an object is its capability of producing a force that can do work and also its capability of transferring heat. When an object does work on another object, the former’s energy (its capability of doing work) decreases and the latter’s energy increases, by transferring it.'

The start of this text would be at the very top, and the end of it would stop right before [Energy is conserved quantity]

Let me know what you think and feel free use a modified version of this. Thank you for reading.— Preceding unsigned comment added by ElskverdigHug (talkcontribs)

 Not done: Hello! This would definitely be something to get some kind of consensus about before opening an edit request. I've gone ahead and marked the template as answered so as to lower our queue of requested edits. This is not a denial of the suggestion, nor a formal closure of discussion, or anything like that. Feel free to come to my talk page if you have any questions. Cheers! —Sirdog (talk) 02:22, 24 May 2022 (UTC)[reply]

Another form of energy: Biochemical

[edit]

I think Biochemical should be added as another form of energy. It’s different from chemical energy in that it’s unique to living creatures and that’s the main way living things even use energy. There is even a whole field in this called Bioenergetics. HotBallah (talk) 08:52, 24 February 2023 (UTC)[reply]

Agree with Bduke --ChetvornoTALK 20:27, 24 February 2023 (UTC)[reply]

By that logic elastic potential energy is just chemical energy then since it stored in the intermolecular bonds. Or the chemical bonds are just electric potentials etc.

The whole point of the “forms” of energy section is to list different forms that don’t go down to the most basic forces and energy. ATP is a lot more complex than your regular old energy stored in chemical bonds, even IF that’s what it’s entirely made up out of.

When people think of releasing chemical energy they think of something crude like a combustion reaction or something. Not metabolization. HotBallah (talk) 06:55, 25 February 2023 (UTC)[reply]

Whatever. The point is that biologists who work by publish or perish don't deny that ATP is a store of chemical energy, even if the mechanism for extracting such energy is complex.
And bioenergetic therapy is a misleading name for a brand of quackery. Hint: it is all about mystical energies, which were never noticed by mainstream science.
Personally, I'm healthier on a diet of "lacking prana" than on a diet of "rich in prana". Which makes me think that prana is a big load of tosh. tgeorgescu (talk) 07:13, 25 February 2023 (UTC)[reply]

lol ok then HotBallah (talk) 16:07, 25 February 2023 (UTC)[reply]

Semi-protected edit request on 28 August 2023

[edit]

Hi. Can we get "Conserved quantity" in the lead to link to Conserved quantity? 96.227.223.203 (talk) 00:37, 28 August 2023 (UTC)[reply]

 Not done for now: please establish a consensus for this alteration before using the {{Edit semi-protected}} template. This currently links to Conservation law, which seems to me to be more directly related to energy. The Conserved quantity page is about the general concept, which is broader than its specific use in physics. So I'd say there should be more input from other editors before changing this. -- Pinchme123 (talk) 03:58, 28 August 2023 (UTC)[reply]

Semi-protected edit request on 17 October 2023

[edit]

The caption for the main image incorrectly links to the article for plasma lamp while it should be linking to the article for plasma globe:

Proposed change – infoboxes are quite long so collapsed by Tollens (talk) 22:07, 17 October 2023 (UTC)[reply]

change

Energy
A plasma lamp, using electrical energy to create plasma, light, heat, movement and a faint sound
Common symbols
E
SI unitjoule
Other units
kW⋅h, BTU, calorie, eV, erg, foot-pound
In SI base unitsJ = kg⋅m2⋅s−2
Extensive?yes
Conserved?yes
DimensionM L2 T−2

to

Energy
A plasma globe, using electrical energy to create plasma, light, heat, movement and a faint sound.
Common symbols
E
SI unitjoule
Other units
kW⋅h, BTU, calorie, eV, erg, foot-pound
In SI base unitsJ = kg⋅m2⋅s−2
Extensive?yes
Conserved?yes
DimensionM L2 T−2

It might make sense to also change the name of the image to more accurately reflect the subject portrayed. JosephCoston (talk) 21:27, 17 October 2023 (UTC)[reply]

 Done Tollens (talk) 22:04, 17 October 2023 (UTC)[reply]

Should this page include references to Entropy?

[edit]

I don't see that including references to entropy on this page adds to the understanding of Energy. Gpsanimator (talk) 00:28, 8 August 2024 (UTC)[reply]

Entropy is one of two components of free energy, a key idea of chemical energy, and is also related to several aspects of thermal energy. It also relates to multiple aspects of thermocdynamics in general (see several previous talkpage discussions). DMacks (talk) 04:26, 12 August 2024 (UTC)[reply]
I think your argument is flawed:
1.What, in classical or new physics is "free energy"? Justifying the presence of Entropy on the Energy page on that basis is very poor logic.
2. There are at least two independent interpretations of entropy: one from the subjective identification of the number of micro-states in a macro-state (whatever they are!), and one from the thermodynamics of an irreversible process. Neither can be deduced from the other.
Any discussion about entropy should be on the Entropy page. Leaving it on the energy page is a big mistake. Gpsanimator (talk) 02:47, 18 August 2024 (UTC)[reply]
  1. See Thermodynamic free energy.
  2. What? Entropy having a distinct sense in statistical mechanics doesn't negate the relevance of using the word for its sense in thermodynamics. It is perfectly justified to include summary discussions of related subjects in this way, as they are often needed for a holistic understanding of a topic.
Remsense ‥  02:53, 18 August 2024 (UTC)[reply]
Supporting a challenge to a Wiki article by quoting another Wiki article is nonsense. Energy is a clearly identified physical property. Entropy is not.
Of course it negates the relevance: In science, you can't have two independent properties with the same name! Gpsanimator (talk) 02:58, 18 August 2024 (UTC)[reply]
You asked what something was, and the article is about what it is. That's just me trying to answer the very basic question you asked, regardless of what it supports.

In science, you can't have two independent properties with the same name!

Wikipedia is a general encyclopedia, not whatever restrictive genre you're speaking about where every word has exactly one meaning. Remsense ‥  03:01, 18 August 2024 (UTC)[reply]
I think you may be channelling Humpty Dumpty in Through the Looking Glass :
"When I use a word," Humpty Dumpty said, in rather a scornful tone, "it means just what I choose it to mean — neither more nor less." 
The language of science is indeed " a restrictive genre ... where every word has exactly one meaning."
Ponder that for a minute before posting any further nonsense. Gpsanimator (talk) 03:49, 18 August 2024 (UTC)[reply]
Au contraire—as it pertains to site policy, we use words the way sources use them, so please keep that in mind before any further edits based on your very particular perspective on how language must be be used. Remsense ‥  04:45, 18 August 2024 (UTC)[reply]
And there's my problem. "Sources" use entropy in two totally incompatible senses. That tautology should be argued out in an Entropy forum, not here. We should be smart enough to see the elephant in the room and avoid references to such a challenged concept. Gpsanimator (talk) 06:16, 18 August 2024 (UTC)[reply]
They are not incompatible, but merely logically independent. It is obvious to most people which sense is meant with a bit of context. To be clear, if you want to make a case for removing this material, you need to cite people who are saying it's a problem or that entropy is not an important concept for a generalized understanding of energy. Can you point to anyone in the literature who has these same worries about use of the word "entropy", or is this your own deduction? Remsense ‥  06:19, 18 August 2024 (UTC)[reply]
Also wait, I'm sorry—I've just looked into this properly, it's been a while—what do you mean they are incompatible? Remsense ‥  06:21, 18 August 2024 (UTC)[reply]
"Can you point to anyone in the literature who has these same worries about use of the word "entropy? Not many, but those who do are worth listening to Check Sabine Hossenfelder YT (can't post the link)
Incompatible? yeah: find anyone who can rationalise micro- and macro-states with thermodynamic energy balance!
(P.S. this discussion should be on a the Entropy Talk page, not the Energy Talk page!) Gpsanimator (talk) 06:51, 18 August 2024 (UTC)[reply]
Unfortunately, this seems to be your personal hang-up unless you can cite any reliable sources that corroborate that this is actually a problem, since we don't write articles based on our personal favorite interpretations. Remsense ‥  07:00, 18 August 2024 (UTC)[reply]

Зачувување на енергијата

[edit]

Фактот дека енергијата не може да се создаде ниту да се уништи се нарекува закон за зачувување на енергијата. Првиот закон на термодинамиката, вели дека енергијата на затворениот систем е константна, освен ако енергијата не се пренесува преку границите на системот во форма на работа или топлина и енергијата не се губи при преносот. Вкупниот влез на енергија во системот мора да биде еднаков на вкупниот излез на енергија од системот, плус промената на енергијата присутна во системот. Секогаш кога некој ја мери (или пресметува) вкупната енергија на систем на честички чии взаемни дејства не зависат експлицитно од времето, се забележува дека вкупната енергија на системот секогаш останува константна.

Додека топлината секогаш може целосно да се претвори во работа во реверзибилна изотермична експанзија на идеален гас, за циклични процеси од практичен интерес кај топлинските мотори, вториот закон на термодинамиката, вели дека системот секогаш губи енергија како отпадна топлина. Ова создава ограничување на количината на топлинска енергија која може да работи во цикличен процес, наречено достапна енергија. Механичките и другите форми на енергија можат да се трансформираат во друга насока во топлинска енергија без такви ограничувања. Вкупната енергија на системот може да се пресмета со собирање на сите форми на енергија во системот. Ричард Фајнман (Richard Feynman) изјавил за време на предавање во 1961 година:

Постои факт, или ако сакате, закон, кој ги регулира сите природни феномени кои се познати до денес. Не постои исклучок од овој закон – како што знаеме, барем до сега. Законот се нарекува зачувување на енергијата. Тој вели дека постои одредена количина, која ја нарекуваме енергија, која не се менува во многубројните промени кои ги претрпува природата. Тоа е најапстрактна идеја, бидејќи е математички принцип; вели дека постои нумеричка количина која не се менува кога нешто се случува. Тоа не е опис на механизам, или нешто конкретно; интересен факт е дека можеме да пресметаме некој број, и откако ќе завршиме гледајќи ја природата како ги изведува своите трикови, повторно го пресметаме бројот, резултатот е ист. — Фајнмановите предавања по физика

Повеќето видови на енергија (со исклучок на гравитационата енергија) се исто така предмет на строги локални закони за зачувување. Во овој случај, енергијата може да се разменува само помеѓу соседните региони на просторот, и сите набљудувачи се согласуваат за волуметриската густина на енергијата во било кој даден простор. Исто така, постои и глобален закон за зачувување на енергијата, кој вели дека вкупната енергија на универзумот не може да се промени; ова е последица на локалниот закон, но не и обратно.

Овој закон е фундаментален принцип на физиката. Како што е прикажано ригорозно од страна на теоремата на Нетер, зачувувањето на енергијата е математичка последица на транслационата симетрија на времето, својство на повеќето феномени под космичката скала што ги прави независни од нивната местоположба на временската координата. Вчера, денес и утре физички не се разликуваат. Ова е поради тоа што енергијата е количината која е канонично конјугирана со времето. Ова математичко испреплетување на енергија и време, исто така, резултира со принципот на неизвесност – невозможно е да се дефинира точната количина на енергија за време на одреден временски интервал (иако ова е значајно само за многу кратки временски интервали). Принципот на неизвесност не треба да се меша со зачувувањето на енергијата, туку обезбедува математички граници до кои енергијата може да се дефинира и измери.

Секоја од основните сили на природата е поврзана со различен тип на потенцијална енергија, и сите видови на потенцијална енергија (како и сите други видови на енергија) се појавуваат како систем маса, кога и да се присутни. На пример, компресирана пружина ќе биде помасивна отколку пред да биде компресирана. Исто така, секогаш кога енергијата се пренесува помеѓу системите со помош на било кој механизам, со него се пренесува поврзана маса. Во квантната механика енергијата се изразува со помош на Хамилтоновиот оператор. На било која временска скала, неопределеноста на енергијата по форма е слична на Хајзенберговиот принцип на неопределеност (но, не е математички еквивалентен на него, бидејќи H и t не се динамички коњугирани променливи, ниту во класичната ниту во квантната механика). Во честичната физика, оваа нееднаквост овозможува квалитативно разбирање на виртуелните честички, кои носат импулс. Размената на виртуелни честички со реални честички е одговорна за создавање на сите познати фундаментални сили (поточно познати како фундаментални заемнидејства). Виртуелните фотони се исто така одговорни за електростатското заемнодејство помеѓу електричните полнежи (што резултира во Кулоновиот закон), за спонтаното зрачно распаѓање на возбудените атомски и нуклеарни состојби, за Касимировата сила, за Ван дер Валсовата сила и некои други видливи појави. Angela Sazdova (talk) 15:49, 3 November 2024 (UTC)[reply]