Talk:Right-hand rule

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New diagram[edit]

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! 21:33, 28 July 2007 (UTC)

Screws are when I use the rule most[edit]

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 (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.)
    --Jerzyt 09:44, 29 April 2009 (UTC)

Direction associated with Rotation[edit]

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[edit]

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[edit]

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[edit]

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?[edit]

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" 05:24, 20 February 2007 (UTC)

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

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 (talk) 22:39, 7 March 2007 (UTC).

This article needs cleaning[edit]

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 (talk) 14:31, 2 November 2013 (UTC)

Right hand rules[edit]

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)

Merge with Right hand grip rule?[edit]

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. 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".
--Jerzyt 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. --ChetvornoTALK 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[edit]

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)

Picture is inconsistent with what is shown on the Cross product page[edit]

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 (talkcontribs) 22:56, 24 July 2009 (UTC)

Replace left and right hand rules with left and right turning screw[edit]

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. --ChetvornoTALK 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.Valchemishnuʘ 12:44, 11 September 2011 (UTC)

Uhnacceptable merging: Is this enough?[edit]

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:

From NCERT Science textbook for class 10

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

Maxwell’s corkscrew rule[edit]

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.Valchemishnuʘ 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.Valchemishnuʘ 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)

Electron Deflection[edit]

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)


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"? (talk) 09:10, 15 April 2012 (UTC)

Left-hand Rule on Right-hand Rule page[edit]

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 (talk) 06:25, 1 October 2012 (UTC)

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

Two-Hand Rule.png

..."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:

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[edit]

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)