Talk:Right-hand rule

Overly complex language

The purpose of the right hand rule is to make it EASY almost TRIVIAL to realise is or will happen in a situation. The language used to describe the rule is way to complex to be easily understood. This page is far from being one of the best pages on wikipedia. — Preceding unsigned comment added by 110.174.175.94 (talk) 23:26, 11 January 2015 (UTC)

New diagram

The existing diagram is problematic in that the orientation of the axies is ambiguous since each is just a line. It needs something more to make them pop out. —BenFrantzDale 04:41, 3 March 2006 (UTC)

Is this better? –Gustavb 03:56, 12 March 2006 (UTC)

YES! MUCH BETTER! 67.62.240.136 21:33, 28 July 2007 (UTC)

Screws are when I use the rule most

Vehicle: Well, on the other side of the vehicle it is different! Also mention that how some of us remember how to turn a screw is to stick up our right thumb... --User:Jidanni 2006-04-20 —Preceding unsigned comment added by 210.200.105.231 (talk) 17:06, 19 April 2006

• Some but not all vehicles use lugs or bolts with left-handed threads on one side. (I presume because the torque the wheel experiences during braking can slightly rotate the wheel relative to the hub, and the resulting torques on the nut or bolt are slightly higher on their outer edges than their inner ones, due to the greater distance from the center of the axle, and it's possible for the net force to overcome friction and slightly loosen the threads; using the thread that makes braking tighten rather than loosen them prevents a dangerous accumulation of the loosening.)
  --Jerzy•t 09:44, 29 April 2009 (UTC)
  

Direction associated with Rotation

Change "shortest" to "shorter" and "over" to "through"

There are two and only two possible arcs for measuring the angle from a to b, one sweeping clockwise, the other counterclockwise. With only two possibilities "shorter" is the appropriate adjective. If clockwise sweep is shorter, then counterclockwise sweep is longer, and vice-versa. "through" is probably is a better usage compared to "over". Subhash 23:41, 16 June 2006 (UTC)

Direction associated with Rotation

Add "clockwise and counterclockwise"

There are two and only two possible rotations in the coordinate planes: so at least for engineering computations, these two senses, clockwise and counterclockwise ought to be incorporated in the definition. Any one inclined to edit this out ought, in the very least state if there are more possibilities in 3-dimensional space, that is 3 coordinate planes. Subhash 00:54, 17 June 2006 (UTC)

Applications of the Right-hand rule

Add phrase "by choosing the shorter angle, 90 degrees clockwise or counterclockwise"

There are two and only two choices in determining y-axis with known or arbitrarily chosen x-axis one rotating 90 degrees clockwise, other 90 degrees counterclockwise. If someone decides to edit this out, he/she has the obligation to suggest other possibilities of determining the y-axis. This edit is in preparation for adding, to this article:

"Alternate Engineering Definition of Left and Right-hand rules for orthogonal Cartesian Coordinate Systems"

and eventually add to the Cross Product article unambiguous and unique correlation between sign of torque and rotational sense, i.e. clockwise or counterclockwise. Subhash 00:55, 17 June 2006 (UTC)

Picture and discussion both correct, but don't cohere, implying bad pedagogy

The forefinger/middle finger/thumb method is described in words as I learned it.

But the color image of the technique shows another variation, where the thumb points in direction of a. That's another correct technique,but it doesn't jive with the words in the text.

I would edit but I can't edit an image very easily.

Third application of right-hand rule?

The article mentions that there are three applications of the rule, but only seems to list two. The edit in which it was added was extremely small, only changing the word "two" to "three"129.123.210.30 05:24, 20 February 2007 (UTC)

"Direction associated with an ordered pair of directions" part is hard to understand

I'm trying to figure out how this rule is supposed to have a purpose. The description of how to make my right hand look like that picture doesn't seem to work out properly. If the thumb is along the a axis in the picture, how does that indicate c? What am I supposed to find out by positioning my hand and fingers this way? —The preceding unsigned comment was added by 203.220.148.78 (talk) 22:39, 7 March 2007 (UTC).

This article needs cleaning

I am not familiar enough with the topic to understand this article in its present form, let alone try and rewrite it. The stuff that is here at the moment is very technical even though it sounds like it is a technique for simplification. Could more specific used be added, as opposed to the generalisation that is present at the moment. Conrad.Irwin 11:15, 5 June 2007 (UTC) Forgot to sign

Agreed, this article is terribly written and, for such a simple topic, so confusing that it is unusable. — Preceding unsigned comment added by 129.31.137.141 (talk) 14:31, 2 November 2013 (UTC)

Right hand rules

These are the four main right hand rules which we learnt in physics. theres probably more though:

1) In a wire (current carrying conductor), the thumb indicates the direction of current, and the fingers wrap around to form the direction of magnetic field.

2) In an electromagnet, the thumb points to the north side of the magnet, and the fingers wrap around to form the direction which the current flows (through the coiled wire).

3) For a wire in an extended field, or for a DC motor, the hand is stretched out such that the thumb and index finger are perpendicular. The thumb indicates the direction of of current, and the fingers indicate the direction of magnetic field. The force applied to the wire is denoted by the "slap" of the palm, that is, the direction which the palm pushes towards.

4) For a generator or a charged particle, the hand is positioned in the same way as in 3). The thumb denotes the velocity, the fingers are magnetic field, and the direction of the "palm slap" is the direction in which the positive charge flows (so if the particle is negatively charged, it moves in the opposite direction). I heart duff 08:07, 11 June 2007 (UTC)

These are all special applications of the same rule. — Laura Scudder ☎ 20:35, 11 June 2007 (UTC)

Let's not forget the right-hand-rule associated with the [[cross

-product]]. !jim 21:30, 21 June 2007 (UTC)what te hell

Merge with Right hand grip rule?

A colleague wrote at talk:Right hand grip rule

Both this page and Right-hand rule say they're "related, yet different", but not how so. In my opinion, the RHGR is just an instance of the RHR, and that should be made clear. But maybe someone had a different view of the RHGR, as it's described as "a physics principle" (which doesn't fit the "rule" part). Would be nice if someone cleared this up. 134.130.4.46 02:07, 10 October 2007 (UTC)

It seems to me as well that unification of the two concepts is in order. In particular, i note that the RHR for the RH coord sys can be rendered, as in the accompanying article, statically via the thumb/index/middle sequence or dynamically, via a RHGR motion around the 3-fold-symmetry axis of the unit pyramid whose three edges converge at the origin and coincide with the three positive half-axes: with thumb along the symmetry axis, the fingers point the direction of a rotation of the unit pyramid in which any edge cycles from X axis to Y axis to Z axis and repeat. I'm not sure how many instances of reducing a use of RHR or RHGR to the other are useful, but one is enuf to pay off the otherwise cryptic claim "related, yet different", and eliminate a separation that, while arguably "real", is nevertheless awkward and unnecessary.
BTW, i remember in writing this that we were taught RHR as the "Right Hand Motor Rule".
--Jerzy•t 10:19, 29 April 2009 (UTC)

I concur with the merger. In my experience the term "right hand grip rule" isn't used much, they are both called the "right hand rule", and as Jersy says are very closely related and should be explained in the same article. --Chetvorno^TALK 14:47, 29 April 2009 (UTC)

Merge. This article already discusses several distinct applications of the human hand as a chiral reference object, consolidating here makes sense to me. Incidentally, the illustrated "grip rule" is the same as the convention for right-twist or left-twist rope/yarn. Although in that case the common mnemonic objects are the letters 'S' and 'Z', for left and right, respectively. --Dfred (talk) 17:33, 29 April 2009 (UTC)

Merge, Chetvorno's experience matches my own --royalfire

Added merge tags. --Dfred (talk) 15:17, 24 May 2009 (UTC)

Split article into Right hand grip rule

Apart from the anthropomrphic coincidence that they both use the right hand, there is no reason to have these two quite distinct rules under the same article. It is significantly confusing to do so. It is particularly odd when the related left & right hand rules are in separate articles, but the quite different grip rule is merged!

The grip rule relates electrical current and magnetic field.

Fleming's right hand rule relates the induction of current due to motion in a field / (LH) the production of a force due to a current.

The use of the hand is coincidence, no more. In one case the open hand is a mnemonic for the orientation of axes in three-space, in the other a clenched hand reminds us of a helical direction. The rules don't even work unless the hand is moved from one position to another!

As the electrical principles are broadly unrelated in their meaning, there is scope for confusion. This is especially so as the rules are just about close enough to be confusable. Andy Dingley (talk) 14:36, 15 February 2011 (UTC)

I agree that the articles should be split. —DIV (120.17.163.66 (talk) 13:38, 13 June 2018 (UTC))

Picture is inconsistent with what is shown on the Cross product page

The picture on the Cross product page shows vector a as the index finger, b as the middle finger, and a cross b as the thumb. The picture on this page defines a and b differently. I believe the picture on the Cross product is more correct, and at least it seems that the two should agree with each other. —Preceding unsigned comment added by Bkerin2 (talk • contribs) 22:56, 24 July 2009 (UTC)

Replace left and right hand rules with left and right turning screw

I do not like this left and right hand rules. In order to apply them, you have to remember the position of 3 elements. When using a screw, it's quite clear where the rotation goes. So there is only one element to remember: right or left turning screw. --Huibc (talk) 16:11, 27 July 2010 (UTC)

Perhaps the "screw" could be introduced (with a picture) as an alternate way to memorize the rule, but I think the "hand" should stay as the primary explanation, because: (1) it is usually explained that way in texts and physics classes, (2) not everyone is familiar with screws and their threads or has access to one, but everyone always has access to a hand (3) the rule is called the right hand rule. --Chetvorno^TALK 07:54, 10 October 2010 (UTC)

Please explain how can we relate a screw rule with a hand rule first. There is no way we can relate the right hand rule and the right hand grip (thump) rule. One (right hand rule) describes the direction of current produced and the other (thump rule) just describes the direction of magnetic field produced when a current moves through a coil. Both are distinct mnemonics. And I don't understand why they merged both and why doesn't anybody explain it with references! Please explain how it can be related, in the article (and on this talk page for us to discuss) with references and clear evidences.Valchemishnu^ʘ 12:44, 11 September 2011 (UTC)

Uhnacceptable merging: Is this enough?

I was totally confused with this article, and I read the article left hand rule only get more confused.I am not able to say anything on this article.

That is why I just provide a source that may help to undo the merging of the article right hand grip rule and Fleming's right hand rule.

From NCERT Textbook for class 10, Science textbook (in English), Chapter 13 Magnetic Effects of Electric Current...

Right-Hand Thumb Rule (page no. 228) A convenient way of finding the direction of magnetic field associated with a current-carrying conductor is – Imagine that you are holding a current-carrying straight conductor in your right hand such that the thumb points towards the direction of current. Then your fingers will wrap around the conductor in the direction of the field lines of the magnetic field... This is known as the right-hand thumb rule. This rule is also called Maxwell’s corkscrew rule. If we consider ourselves driving a corkscrew in the direction of the current, then the direction of the corkscrew is the direction of the magnetic field.

Fleming's right hand rule (Page no. 235) The induced current is found to be the highest when the direction of motion of the coil is at right angles to the magnetic field. In this situation, we can use a simple rule to know the direction of the induced current. Stretch the thumb, forefinger and middle finger of right hand so that they are perpendicular to each other, as shown in Fig. 13.18. If the forefinger indicates the direction of the magnetic field and the thumb shows the direction of motion of conductor, then the middle finger will show the direction of induced current. This simple rule is called Fleming’s right-hand rule.

Online view of book: http://www.iasexams.com/NCERT-Books/NCERTBooksforClass10/FreedownloadClass10ScienceNCERTBook/Class10_Science_Unit13_NCERT_TextBook_EnglishEdition.pdf

From NCERT Science textbook for class 10

Does this make it clear that these two mnemonics are different? Valchemishnu^ʘ 14:12, 11 September 2011 (UTC)

Maxwell’s corkscrew rule

There is no article on wikipedia about Maxwell’s corkscrew rule. This rule is also known as the Right hand thumb rule and Right hand grip rule. However it is distinct from Flemming's Right hand rule!

Are we becoming "mergiholic" affected with merging every article? The article Fleming's Right hand rule for generator redirects to Flemmings left hand rule for motor. and describes nothing much on the former.Valchemishnu^ʘ 14:23, 11 September 2011 (UTC)

I encourage you to de-merge if you see a clear need and you can build the content correctly and cite WP:RSs (which your discussion above suggests that you can). As for mergiholics, yes, I agree that we have some of those around. The only way to defend against them is to try harder than they do (in terms of content development and referencing) and to cite good sources for your rework. If you do it, and really do your best, they usually melt away into the woodwork. They don't admit that they were wrong, they just go find some other content area where they hope to put on their alleged-superiority act and get away with it without being called out and proven wrong. — ¾-10 01:48, 12 September 2011 (UTC)

Thank you Three-quarter-ten for your encouragement and with that I have started to collect information for it. But some of them were disappointing e.g.,[1]. But I will never give up. I know I am not alone and the whole community is along with me. And people like you are invaluable treasures for Wikipedia.Valchemishnu^ʘ 18:59, 23 September 2011 (UTC)

Per Talk:Right-hand_rule#Split_article_into_Right_hand_grip_rule above, I'd agree with you.

I think the left hand & right hand rules can reasonably be placed together, as the underlying physics is comparable and it's just the context of motor or dynamo that differs. The corkscrew rule though is quite different. Andy Dingley (talk) 19:18, 23 September 2011 (UTC)

I am against de-merging any of the rules. All these rules are related, and should be covered in the same article. Besides, it is just easier for readers to untangle the confusing rules if they are all in one place. As the article indicates rather vaguely, the right hand rule, right hand grip rule, Maxwell's corkscrew rule, and Fleming's left hand rule for motors, all come from vector mathematics, and are all part of a single sign convention in vector calculus. Probably the article could do a better job of explaining this.

• The right hand rule giving the direction of current in a generator's windings, comes from Faraday's law of induction giving the direction of EMF induced in a circuit, which comes from the convention that the direction of the curl of a vector field is related to the direction of circulation of the field by the right hand rule.
• Fleming's left hand rule for motors, giving the direction of the force of a magnetic field on a current carrying wire in a motor, comes from the right-handed Lorentz force law giving the force of the magnetic field on a moving charged particle, which comes from the fact that the cross product of two vectors has a direction defined by the right hand rule. The rule became left handed because Fleming reversed the order of fingers representing vectors to make it more consistent with his rule for generators.
• Maxwell's corkscrew rule giving the direction of the magnetic field lines around a current carrying wire, comes from Ampere's circuital law, which is also defined by the direction of the curl of a vector field. The "corkscrew rule" is more frequently defined as another application of the right hand grip rule.
• The right hand grip rule giving the direction of magnetic field created by a coil of wire, just comes from applying Maxwell's corkscrew rule to the current in a loop of wire.

The two mathematical sign conventions all this is based on, the direction of the cross product and direction of the curl, are dependent on each other through Stokes theorem, they are both a single sign convention due to the arbitrary choice by mathematicians of a right-handed coordinate system as standard, instead of left handed. This means if you reversed the handedness of all the laws above, made the right hand laws left handed and vice versa, all the mathematics would still work. --Chetvorno^TALK 22:05, 25 July 2021 (UTC)

Electron Deflection

When impacting a magnetic field (with North up), electrons are deflected to the left as if they were being bounced off a clockwise rotating force field. Does that imply that a magnetic force line can be considered to be a clockwise rotating vortex of some material?WFPM (talk) 22:00, 24 February 2012 (UTC)

4D

How would this be extended to 4 dimensions? Which direction would the fourth axis have to point (if there's even a reasonable way of describing that mathematically). Obviously it wouldn't be able to be represented by a hand, but what's an algebraic way of stating "right-handed system" or "left-handed system"? 69.180.172.142 (talk) 09:10, 15 April 2012 (UTC)

Left-hand Rule on Right-hand Rule page

This is a page for the right-hand rule. There shouldn't be diagrams of the left-hand rules on this page, especially WITHOUT the corrisponding right-hand rule, as is with "Fleming's left-hand rule" diagram.

I suggest, to lessen confustion A new page for the left-hand rule entirely, clearing the left-hand rule off this page, and simply mentioning that the left-hand rules exist (probably in the introduction) Or, Making the page "Hand Rules", and have dedicated subsections for each rule, or each application. — Preceding unsigned comment added by 60.231.45.70 (talk) 06:25, 1 October 2012 (UTC)

To do this please first look at the existing Left-hand rule redirect to Fleming's left-hand rule for motors, and secondly figure out how the relevant content for a left-hand rule article according to your concept can be compatible with the existing article/redirect.

—DIV (120.17.163.66 (talk) 13:41, 13 June 2018 (UTC))

I agree it is confusing to have information about left hand rules in this article, but the truth is all of the rules are related, and it is easier for readers to untangle if they are all described together on one page. Fleming's left-hand rule for motors is inherently confusing because it is based on the Lorentz force law which ironically uses the right hand rule, because the direction of the vector cross product is defined to be right-handed. The rule became left-handed because Fleming reversed the order of fingers representing the vectors to make it more consistent with his generator rule. This should be explained in this article. --Chetvorno^TALK 23:02, 25 July 2021 (UTC)

To be clear, I am not against having the Fleming's left-hand rule for motors page. I just think it is okay to also describe Fleming's left hand rule on this page, and how it is intimately related to the right hand rules. BTW, electromagnetics is a lot easier if you forget about Fleming's left-hand rule and just calculate the force on wires in a motor using the Lorentz force law, which is equivalent but is defined with a right hand rule. Then ALL the directions in electromagnetics are defined by right-hand rules, so you just always use the right-hand rule - easy to remember!!! --Chetvorno^TALK 23:18, 25 July 2021 (UTC)

I have a strange feeling that it will take more than 100 years for scientists to be bored enough to say...

..."Let's add in K. Marinas' Two Hand Rule." I mean, in some respects, this is far more helpful approach in that you don't have to make a weird sign with your fingers, and you get to differentiate between electron current and "conventional current".

Furthermore, if you want to know the direction that current would flow if you moved the lines of a magnet perpendicular through a conductor, all you have to do imagine your thumb as being the magnetic pole, then gently contract your fingers around your thumb when moving your hand down and gently release your fingers straight when moving your hand up. As far as knowing what hand to use for a given pole (N or S) and charge (+ or -), the diagrams on the right show us how using four symbols that I like to call:

"North-Positive" Corresponds to the traditional right-hand rule	a curvaceous N with arrowheads at both ends	CCW from observer point of view - Use Right Hand.
"South-Negative"	a curvaceous S with opposing arrowheads at center	CCW from observer point of view - Use Right Hand.
"North-Negative"	a curvaceous N with opposing arrowheads at center	CW from observer point of view - Use Left Hand.
"South-Positive"	a curvaceous S with arrowheads at both ends	CW from observer point of view - Use Left Hand.

Fortunately N is the first letter for "North" and S the first letter for "South". Had these letters been the other way, the direction would have been completely backwards. Also, had one or both of these letters had been something other than N or S, then the "Two Hand Rule" would not even exist. It's an amazing coincidence, if it is one at all.siNkarma86—Expert Sectioneer of Wikipedia
^{86 = 19+9+14 + karma = 19+9+14 + talk} 10:31, 17 March 2013 (UTC)

Convention vs Physical Phenomenon

At the end of the section "Direction associated with rotation", there is a paragraph stating "The right-hand rule is just a convention. When applying the rule to current in a straight wire for example, the direction of the magnetic field (counterclockwise instead of clockwise when viewed from the tip of the thumb) is a result of this convention and not an underlying physical phenomenon."

First of all, this statement doesn't fit very well under the heading of "Direction associated with rotation".

Second and more importantly, I strongly disagree with this statement. The RHR is used in physics to mimic the behavior of nature. It is not just a convention, and nature doesn't change its mind about the direction of a magnetic field just because we decide to change the convention. We use our right hand as a mnemonic to readily recall what nature does in different situations. The RHR as it's used in physics mimics nature, not the other way around. To put it another way, if you use your left hand, you will not get the same result as nature. Therefore it is more than mere convention, it is a "model" that mimics the way nature works.

For these two reasons, I believe this paragraph should be removed entirely.

Simkn (talk) 00:22, 26 March 2014 (UTC)

Simkn, the sentence at the top is correct. The force exerted by a magnetic field doesn't change with human sign conventions, but the magnetic field itself $\mathbf {B}$ is a special kind of vector called a pseudovector, which means that it's direction is dependent on human choice of a sign convention, the handedness of the coordinate system:

(1)The magnetic field is defined by Ampere's law, in which the direction of the magnetic field lines around a current $\mathbf {I}$ is related to the current direction by the right-hand grip rule

${\begin{aligned}\iint _{\Sigma }\nabla \times \mathbf {B} \,\mathrm {d} \mathbf {S} =\oint _{\partial \Sigma }&\mathbf {B} \cdot \mathrm {d} {\boldsymbol {\ell }}=\mu _{0}\mathbf {I} \\\end{aligned}}$

(2) The force exerted by a magnetic field on a moving charge is defined by the Lorentz force law

$\mathbf {F} =q\mathbf {v} \times \mathbf {B}$

in which the direction of the force $\mathbf {F}$ is related to the velocity of the charge $\mathbf {v}$ and the direction of the magnetic field $\mathbf {B}$ by the right-hand rule, due to the mathematical definition of the cross product.

If the right-hand grip rule and the right-hand rule were both changed to left-handed (this is equivalent to changing to a left-handed coordinate system, or a parity flip in which the right- and left- sides of the Universe are exchanged) all these equations would still work, they would give the correct direction for forces and currents, but the new magnetic field would be defined to be in the opposite direction to the old $\mathbf {B} _{\text{new}}=-\mathbf {B} _{\text{old}}$. So the right-hand rule and the right-hand grip rule are not determined by Nature but are arbitrary choices of the mathematics community. But they are dependent on each other, you can't change one without changing the other. They are both part of a single sign convention used in vector mathematics, which also determines the defined direction of the magnetic field. The Fleming's left-hand rule for motors derives from the Lorentz force law, so it is also dependent on them. --Chetvorno^TALK 08:47, 1 August 2021 (UTC)

Section on 'electrical wire "cutting" magnetic field lines' is incoherent

The section Right hand rules for electrical wire "cutting" magnetic field lines seems to refer to a missing diagram. Even if the diagram was present, the directions for the process are so poorly explained that the non-technically educated readers who come to this page to learn it are going to be baffled. --Chetvorno^TALK 01:52, 12 June 2015 (UTC)

Deleted section. --Chetvorno^TALK 20:07, 17 June 2015 (UTC)

Shouldn't Maxwell get a name check?

As stated above and elsewhere on the internet, plus very vague memories of O Level Physics, Maxwell has a rule on this too so shouldn't he be named checked?

Maxwell's is the corkscrew rule. Ampere's is the grip rule. Fleming's is the three orthogonal fingers rule.

This article is awful and ought to be deleted outright (or stripped into a disambiguation page). It confuses every physical concept it can find, just because they have the same body part as a mnemonic. Andy Dingley (talk) 13:38, 25 September 2017 (UTC)

I agree the article needs a lot of improvement; in particular it should explain where the electromagnetics rules come from. But I don't think it would improve comprehension to give each rule its own page and make this a disambiguation page. All of the electromagnetics rules are related, and it would be good to have them together to explain that. But more importantly, these rules are confusing for general readers, and it will be easier for them to disentangle if all the right-hand rules are in one article. I think Fleming's right-hand rule should be merged here too. --Chetvorno^TALK 20:16, 27 July 2021 (UTC)

Two missing right hand rule diagrams

This article should really show (diagram) two (alternative forms) of the right hand rule for the relationship between F / B / I (or v) in the electromagnetism section (the three fingers version and the two fingers and palm version) Paul S. (talk) 20:47, 16 November 2017 (UTC)

Information about Right-hand rule (removal of information)

Benjamin Trovato, thank you for your 19 contributions to this article. I believe your 19 contributions were made in good faith, with the intention of bettering wikipedia and bettering the "Right-hand rule" article. Unfortunately, some of the information you added was unsourced, poorly sourced, or factually wrong. Please familiarize yourself with WP:NOR. If you believe the information you added was not original research, please provide a reference to a reliable source that supports your claim. Thanks. Brian Everlasting (talk) 18:30, 24 April 2018 (UTC)

I am not aware of any original research and cannot find anything false or self-contradictory. You must be seeing something that I don’t see. Please remove anything false and fix anything that needs correction or improvement. Since I don’t feel like spending a week digging through books, feel free to remove anything not cited, although I would not remove anything unless It is somehow bad. The right- and left-hand rules exist to deal with handedness and we must briefly describe the cases before giving the rules. Things with handedness are coordinates, rotations and spirals, electromagnetic fields, vector cross products and others. Mirror images and chirality are over my head. Benjamin Trovato (talk) 14:37, 25 April 2018 (UTC)

The reason I removed the information was that it was not cited, and it was bad. Please keep your personal beliefs in your sandbox. Thanks. Brian Everlasting (talk) 03:26, 26 April 2018 (UTC)

I was unaware that co-ordinates and screws do not have right and left hand rules. Could you direct me to a book that would correct my ignorance?Benjamin Trovato (talk) 03:47, 28 April 2018 (UTC)

Sure, thanks for asking. I would love to correct your ignorance. Before I correct your ignorance, could you please explain to me exactly what it is that you are ignorant about? Brian Everlasting (talk) 07:26, 28 April 2018 (UTC)

I thought that co-ordinates and screws have right and left hand forms, as in the linked articles. I also thought that the rotation axis can be right or left handed and you need to know which to compute the torque. Benjamin Trovato (talk) 20:23, 30 April 2018 (UTC)

I have been waiting three weeks to have my ignorance corrected. I would be inclined to restore the information unless someone has a better idea.Benjamin Trovato (talk) 03:21, 25 May 2018 (UTC)

Restored.Benjamin Trovato (talk) 23:14, 6 June 2018 (UTC). Someone else removed this without explanation, so I give up. Benjamin Trovato (talk) 00:15, 15 June 2018 (UTC)

I am restoring this information because at least 20 pages depend on it for a simple explanation of handedness. If someone seriously thinks that coordinates and rotations do not have handedness, please explain here before removing. Thank you.Benjamin Trovato (talk) 22:18, 21 July 2018 (UTC)

I consulted with Dr Stacy Kenny about this issue and I am waiting for an explanation from Stacy. Hopefully Stacy will publish an answer on Twitter that I can reference. Brian Everlasting (talk) 01:48, 25 February 2019 (UTC)

Handedness of curvilinear coordinate systems

At Spherical_coordinate_system#Conventions there are references to various spherical coordinate system parameterisations that are claimed to lead to either a left-handed coordinate system or a right-handed coordinate system, with a link to this article.
However, the present article suffers from two problems:

• it is a mish-mash of various meanings of "right-hand rule", such as for flow of electricity;
• the text germane to coordinate systems tacitly assumes that the coordinate system must be Cartesian, not curvilinear.

If it is possible to define the handedness of curvilinear coordinate systems, then the definition and adequate explanation should be provided in this article. —DIV (120.17.163.66 (talk) 13:36, 13 June 2018 (UTC))

This article had a description of left- and right-handed coordinates, but someone removed it. See history section, article status as of 06jun. Wikipedia no longer has a clear account of handedness that I am aware of. Benjamin Trovato (talk) 00:38, 15 June 2018 (UTC)

Right-hand rule: Clarification on the permutationally cyclic aspects

The present article reads

"For right-handed coordinates the right thumb points along the z axis in the positive direction and the curling motion of the fingers of the right hand represents a motion from the first or x axis to the second or y axis."

The "Cartesian coordinate system" article reads

"If the index finger of the right hand is pointed forward, the middle finger bent inward at a right angle to it, and the thumb placed at a right angle to both, the three fingers indicate the relative orientation of the x-, y-, and z-axes in a right-handed system. The thumb indicates the x-axis, the index finger the y-axis and the middle finger the z-axis."

George Rodney Maruri Game (talk) 05:20, 24 December 2022 (UTC)

These two definitions are equivalent. If you cyclicly permute the axes of a right-handed coordinate system, the result is another right-handed coordinate system; (x,y,z), (y,z,x), and (z,x,y) are all right-handed if one of them is (Lee, p.18, Andrews, p.150) So changing the 2nd definition to: "the thumb indicates the z-axis, the index finger the x-axis, and the middle finger the y-axis" also gives the right hand rule and is identical to the first definition: this can be seen if you curl the index finger representing the x-axis to be parallel to the middle finger y-axis. --Chetvorno^TALK 06:30, 24 December 2022 (UTC)

Use of the word "Mnemonic"

The opening sentence reads (emphasis mine) "In mathematics and physics, the right-hand rule is a common mnemonic for understanding the orientation of axes in three-dimensional space." Is "mnemonic" the correct word here? I think it is more of a convention. There is an alternate reality somewhere that use a "left hand rule" and they are just as correct as we are, they just happen to have defined a different convention. 50.34.92.170 (talk) 22:40, 25 May 2023 (UTC)

Poor explanations

"The sequence is often: index finger, middle finger, thumb. Two other sequences also work because they preserve the cycle". What does this even mean? What sequence? What cycle? What is the table in the coordinates section trying to say? The rule is not explained well in that section. It does not convey what you are supposed to do with your hand and what your fingers represent in an understandable manner. "For right-handed coordinates, the right thumb points along the z-axis in the positive direction and the curling motion of the fingers of the right hand represents a motion from the first or x-axis to the second or y-axis." How are you supposed to orient your hand? Thumb towards the sky? Towards you? Once you got the right position down (which is not explained) what does each finger represent? How is each finger positioned relative to each other? What fingers do you use? Once you've got everything down, what have you accomplished? Putting some pictures would also be a good idea. All it takes is for someone to take a photo of their hand while they use the rule and put it on the webpage. I would like to do that stuff myself, but I have no idea what the right hand rule even is. TheGoatOfSparta (talk) 11:22, 28 June 2023 (UTC)

All the "cycle" bit is saying is that there are three equivalent ways to represent these vectors with your hand. Notice how the last two sequences are just formed by moving the the first finger to the last, the last to the second etc. - you haven't actually changed the relationship between the vectors you wish to represent, you've just chosen different fingers. I agree this is awkward wording, but I can't think of anything better off the top of my head. Maybe there is a more concise relationship given by the Levi-Civita symbol?

Re: how you are supposed to orient your hand, it doesn't matter - whatever you want to call "the positive z-axis" defines what you do. Coordinate systems being relative to the problem at hand and all. In math you are usually given a coordinate system, in physics you are free to pick.

What the vectors represent depend also on the problem at hand. In a mathematical context, you are usually given the first two vectors and the third represents the orientation of the area vector of the parallelogram formed by the span of the first two vectors. In a physical context it gets a little trickier - what quantities are in your cross product formula inform that. The main goal is just to figure out the direction of vector generated from a cross product though.

If you can provide some more specific examples of wording you think is awkward, I'd be happy to discuss it more. Thanks, RaisedArizona (talk) 17:00, 28 June 2023 (UTC)

Thanks for the reply, but I honestly did not understand anything about it. I don't know what a levi-civita symbol is, but I don't think it is necessary for explaining the right hand rule. I feel like this is supposed to be simple. "All the "cycle" bit is saying is that there are three equivalent ways to represent these vectors with your hand." What vectors? For the cross product? I know a right hand rule for cross products but it is completely different. Draw the vectors tail to tail, karate chop the first vector of the operation while keeping your thumb outstretched and your fingers pointing in the same direction of the vector, curl your fingers towards the second vector, your thumb points towards the direction of the resulting vector. "Notice how the last two sequences are just formed by moving the the first finger to the last", the words first and last have no meaning on their own. If I told you I am first you'd ask me "first of what" because I haven't given you any information by telling you I am first. Which finger is first? The first from the right? Left? Most importantly, I still don't know how to position my fingers for the right hand rule (pictures would be good). Or what the rule is used for in the case of the axes orientation (the other uses don't interest for the time being). "In a mathematical context, you are usually given the first two vectors and the third represents the orientation of the area vector of the parallelogram formed by the span of the first two vectors" don't know what this part mean, it is better if we stick to axes and cross products which I know. "whatever you want to call "the positive z-axis" defines what you do." When you say "whatever", you mean whatever finger? The article says that the thumb is the z axis though for the right hand rule for axis. What do you mean by "defines what you do"? You also said orientation does not matter, but I think I understand what the article is saying about how to position the hand for the right hand rule for axes orientation and the orientation of the hand matters. It is saying to point with your right arm towards your right, do that the whole arm is horizontal, to have the palm facing up and the thumb facing towards you and all the fingers stretched. The fingers represent the positive horizontal axis, the thumb represents the positive front back axis, and curling the fingers halfway so that they point upwards represents the positive vertical axis. This is the default combination of positive parts of the axis for a right handed coordinate system. [Edit: the process I just described to find the base combination of positive axes for right handed systems is correct, but I don't think it is the same process described in the article. I think in the article the process is different from mine in that the palm is facing away from yourself, the rest is the same. The process described in the article should be correct too. This edit is not about my following explanation, but the one just before the edit.] About that, I read a bit online and I think I understood what a right handed coordinate system is. If we have a 3d coordinate system, we know that one half of each axis is positive and the other is negative. A "base/default“, conventional, and arbitrary combination of positions for the positive parts of the axes is defined as right handed. This combination of positions is: the upper part of the vertical axis is positive, the right part of the side to side axis is positive and the back part of the front back axis is positive. Any rigid rotation of the whole coordinate system by any angle preserves the right handedness. A left handed coordinate system has just one change in the "base" combination: the positive parts of the front back axis is in the front. Once again, rotations preserve handedness. In this case, the right hand rule seems to be used to remember the default combination for the right handed coordinate system: palm facing yourself, index and thumb outstretched, middle finger half-stretched pointing to yourself; the fingers all represent positive parts of the axes. When doing this with the left hand to find the base combination for left handed coordinate systems, do everything the same except have the palm facing away from you and the middle finger therefore pointing away from you. TheGoatOfSparta (talk) 23:54, 28 June 2023 (UTC)

First off, easy on the WP:WALLOFTEXT there. I think I get what you are saying though.

The Levi-Civita formalism isn't strictly necessary here (it's just the tensor calc definition of a cross product), I was just suggesting off the top of my head that that might explain the cyclic property more concisely than the previous wording. I think the response you got in the other reply was better though - it's really just a choice of labeling, or equivalently, rigid rotations of the basis.

The cross product for vectors and axes are exactly the same - I'm a little confused by your explanation of your method. Every axis has a basis vector attached, so the cross product must function exactly the same for both objects.

A large part of what I was saying (and what makes this article a little tricky to word properly) is that there is a lot of freedom in terms of how you wish to orient your coordinate system. You say that you aren't interested in some of the applications or references I bring up, but it's important to note how varied the explanation and use cases can be for this rule. That's exactly why what is a very simple technique in practice is very hard to write a concise, encyclopedic article about, without missing any of the various explanations that are used for it across the literature.

Re: the handedness of coordinate systems - I agree. I think this article could do with some major rewrites centering the idea of coordinate systems having a handedness innate to them, and emphasizing that all that is happening in any of these cases is just a cross product. Paradoxically, I feel like the article would be more clear if it was more mathematically explicit with what was happening and why, rather than seemingly shying away from the (relatively simple - upper division undergrad) math needed to properly explain it from the get go. RaisedArizona (talk) 02:37, 29 June 2023 (UTC)

I just want to clear one thing and it's what I wrote in my edit in square brackets. The process described in that edit should actually result in a left handed coordinate system [edit: I hate correcting myself all the time but the process actually resulted in a right handed system using the labeling in the article, so it was a totally legit explanation, along with the one I am about to give], so I suppose that it is still not what the article wants me to do with my fingers. At this point I have no idea what the article wants me to do with the curled fingers right hand rule (not the index middle finger and thumb one). Btw do you get notified when I edit my post here? [Edit: I think I figured out what the article wants you to do in the axes section. All fingers outstretched, palm facing towards yourself fingers pointing to your left. The thumb is the positive vertical axis, your outstretched fingers are the positive side to side axis, and when you curl them halfway they are the positive front back axis. This is indeed a right handed system, but what throws me off is that it is not the standard one. Who uses the left side of the side to side axis as positive? Absolutely nobody. To be fair that is more like the positive vertical axis rotated 90 degrees and relabeled... Let me explain. The usual right handed configuration is positive vertical axis up, positive side to side axis to the right, positive front back axis to the back, let's label them x, y, z. To do this with your fingers, look at your palm, outstretch your index and thumb, and stretch halfway your middle finger so that it points towards you. Now let's rotate them 90 degrees left. Now y is the side to side positive axis and x is the positive vertical axis. Right handed, but who labels them like that? So in the article they are relabeled: z is the vertical positive axis, x is the side to side positive axis and y is the front back positive axis (still a non standard labeling imo). This relabeling preserves the right handedness. But we have a problem... This is definitely non standard. Nobody uses the left part of the side to side axis as negative. I would change that whole thing with the finger positions I described here "To do this with your fingers, look at your palm, outstretch your index and thumb, and stretch halfway your middle finger so that it points towards you." But I am knew here and I don't want to go changing stuff, so I kinda need some "permission" from someone more experienced so that I don't feel like I'm butchering an article.

TheGoatOfSparta (talk) 10:53, 29 June 2023 (UTC)

I reply again because I realized something important and it is that as long as the thumb is pointing upwards and it is the z axis there are at least three (comfortable) different ways to use the right hand rule with finger curling described in the article. One of them is pretty standard (debatable actually), so I suppose the article is talking about that one, which I will describe here since I don't think I described it already. Palm facing away from you, all fingers outstretched and pointing to your right. Thumb is z axis, fingers are x axis. Curling them halfway, they become the y axis. That's what the article is saying probably. I'm pretty confident about this so I hope I won't correct myself again, since I'm polluting this thread with all my edits and corrections. If any explanations are summaries are needed I'll be happy to give them since this thread is a mess to read (my fault). Anyways I still think I can make the article more understandable, but I need backing from a more experienced wikipedia account in the form of a permission to do it. TheGoatOfSparta (talk) 11:44, 29 June 2023 (UTC)

The labeling of the axes given in the article, specifically the third picture, is standard - I can agree that the picture is a little awkward (the positive xy-plane facing away from the viewer makes it tough to duplicate the rotation that is indicated) but that is the only naming of the axes I have ever seen.

The impression I am getting here is that you were taught the right-hand rule in a pretty nonstandard way. There's nothing wrong with that of course, but that might be the source of your confusion with the article - I've been taught this myself probably at least a dozen separate times, and the explanations given in the article are consistent with what I've learned. I have good reason to believe that the text of the article is standard.

You don't need anyone's permission to make edits (and I've only been on Wikipedia for like a week myself anyway), but unless you can provide a concise and specific change you want to make, free from a wall of text and properly formatted, I really can't help you sort out what makes the most sense. My current inclination is that nothing needs to be changed, past the conceptual restructuring I mentioned in my last reply. And yes, I do get notified when you edit your comments. RaisedArizona (talk) 11:52, 29 June 2023 (UTC)

For you the positive z axis pointing upwards is standard? From what I have seen on the web it is usually the positive y axis pointing upwards and the positive z axis pointing backwards. I actually haven't been taught the right hand rule at all. I searched for it on the internet and I came up with like three different ones... I'm happy with the cross product one I learned because it makes sense. But honestly I am still confused about something. Is the use of the right hand rule for axes orientation to distinguish right handed from left handed systems in general or to remember a standard orientation of axes (such as the one I described at the start of this reply), which is also right handed? Anyways, I think I might make some changes for clarity, maybe add pictures I take of my own hands. But first I would like you to check the pictures to see if they are harmonious with the article's explanation. I will post them shortly as a reply [edit: change of plans, taking photos of my hands by myself was awkward (photos weren't good) and it would be complicated to properly add the axes on top of my fingers due to the fact that I am working with a 3d concept on a 2d image. A word explanation might be better. I'll see what I can do]

TheGoatOfSparta (talk) 12:04, 29 June 2023 (UTC)

The way you described is only used when you are generating a 3d coordinate space from the xy-plane - you leave the plane in place, but just add in an extra axis that points into and out of the board. When you are working in 3d coordinates natively (which this article rightly assumes), the z-axis is conventionally chosen to point vertically.

I honestly don't think the right hand rule is used for either remembering handedness or axis position - I've only ever used it for cross products. 3d Cartesian coordinates are mutually orthogonal, so I think using the right-hand rule is a bit unnecessary for the axis position (if you have any two axes, the third is just orthogonal to the plane of those two). Handedness of the coordinate system usually isn't discussed in my experience, it's just taken as convention - I suppose you could use the right or left hand rules to remember this, but that's not the primary use case.

I'm really not sure more pictures are necessary - the pictures that are in the article already describe the different ways of executing the right hand rule that are given. I would support any text edits that clear things up though.RaisedArizona (talk) 13:17, 29 June 2023 (UTC)

TheGoatOfSparta (talk) 13:28, 29 June 2023 (UTC)

I reread what you said and I wanted to point out that when I said orientation I meant where the positive parts of the axes are. Also handedness is important; in left handed systems the right hand rule for cross products won't work.

I would like to share the edits with someone that could tell me whether they comply with all the rules of Wikipedia. Can you do that? It's a small text, shouldn't be too much of a bother. Let me know if you can check the text, I can share it with you through Google drive? Pasting it here doesn't work so I'd have to use another way. TheGoatOfSparta (talk) 13:53, 29 June 2023 (UTC)

Got it. Btw I wanted to paste here the text I wrote that I would like to substitute the current text under the section about axes orientation with. I am working on mobile so I had to paste it in chunks because it would not copy it all at once. However when I do that the text box in which we write replies behaves weirdly. The preview shows only the first chunk of text I pasted, and when I paste all of them and try to press enter at the bottom of the whole text to start a new line it starts a new line at the top or other part near the top instead of the bottom. [Edit: tried pasting everything in docs and copying it again and this time it let me copy it all at once. It was wikipedia that wouldn't let me copy all the text at once, so I had to copy it in chunks; the problem was not with my phone. Tried pasting it all at once in my wikipedia reply and it behaved the same way as before. I'll try to post it and see what happens.] [2nd edit: did you see what happened? The reply in which I pasted the text I wanted to show you is void of text (except for my username etc.)]

TheGoatOfSparta (talk) 13:23, 29 June 2023 (UTC)

I should mostly be able to help with that, yes. You need to share whatever edits you want to make in this forum - given what we've discussed, it should be short enough that you can just retype it as a comment (while being specific about where the edit(s) you are providing would occur). RaisedArizona (talk) 15:08, 29 June 2023 (UTC)

@TheGoatOfSparta: In other words, if you hold your thumb, index finger, and middle finger in the positions shown in the top drawing in the article, and label them in any of the following ways:

Label them:	Or:	Or:
Thumb = X	Thumb = Y	Thumb = Z
Index = Y	Index = Z	Index = X
Middle = Z	Middle = X	Middle = Y

the result is a right-hand coordinate system. It doesn't matter how your arm is positioned. --Chetvorno^TALK 00:36, 29 June 2023 (UTC)

It is right handed, now I understand, but it is not the standard orientation of positive axes used. To see what I mean check my last reply to RaisedArizona. [Edit: it is actually (debatable) a standard orientation of axes as explained in my very last reply, which offers the interpretation of the article that I am happiest with. When I first posted this reply I asked you to check what was my last reply to RaisedArizona at that time (it is not the last anymore), but don't bother with that unless you want to, because I have replaced the explanation in that reply with my last reply as of now.]

TheGoatOfSparta (talk) 11:21, 29 June 2023 (UTC)