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malar
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Join Date: Dec 2010
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Thumb Rule

12/04/2010 9:34 AM

is it a fact that right hand thumb rule is the only rule for showing the relation between the current and magnetism my question is -WHY DO WE NEED TO HOLD THE CONDUCTOR IN RIGHT HAND WHY NOT IN THE LEFT HAND AND EXPLAIN IT............
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lyn
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#1

Re: thumb rule

12/04/2010 9:41 AM

DON'T WASTE OUR TIME WITH THIS NON-SENSE!
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malar
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#2
In reply to #1

Re: thumb rule

12/04/2010 9:47 AM

VERY GOOD ANSWER
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phoenix911
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#3

Re: thumb rule

12/04/2010 10:08 AM

one finger points to the direction of current. The other points to the direction of lines of magnetic flux

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lyn
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#4
In reply to #3

Re: thumb rule

12/04/2010 10:09 AM
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malar
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#5
In reply to #3

Re: thumb rule

12/04/2010 10:13 AM

u r wright buddy my question is y it has to be right hand???
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Anonymous Poster
#6
In reply to #5

Re: thumb rule

12/04/2010 10:23 AM

Dont you know when and for what, you should use your left hand and your right hand.
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lyn
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#7
In reply to #5

Re: thumb rule

12/04/2010 10:24 AM

Although I don't normally respond to poorly worded and grossly misspelled questions, since I have a witty response, I'll make an exception.

"my question is y it has to be right hand???"

That's only in the northern hemisphere. In the southern hemisphere, you'd hold it in your left hand.

Coriolis effect - Wikipedia, the free encyclopedia
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Hendrik
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#8
In reply to #7

Re: thumb rule

12/04/2010 10:38 AM

Now it is only a matter of finding the magnetic drain pipe to install a magnetic whirlpool generator.

It may produce minus 220/110 volt - how do one reverse the polarity?

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lyn
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#9
In reply to #8

Re: thumb rule

12/04/2010 10:40 AM

Turn the drain pipe over?
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Anonymous Poster
#11
In reply to #9

Re: thumb rule

12/04/2010 10:50 AM

Can that be patented?
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malar
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#10
In reply to #8

Re: thumb rule

12/04/2010 10:48 AM

reverse the supply of the generator
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malar
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#13
In reply to #7

Re: thumb rule

12/04/2010 10:54 AM

but still right hand thumb rule ha?? in any hemisphere or any part of the earth this right hand thumb rule is the rule explaining the relation between the relation between the electric field and magnetism.. and also coriolis effect explain only the movement of the object....
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lyn
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#15
In reply to #13

Re: thumb rule

12/04/2010 10:58 AM

Never mind. This is boring.
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phoenix911
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#28
In reply to #5

Re: thumb rule

12/04/2010 5:25 PM

depends on your perspective, but.........with your right hand the flux will be going ccw with the current flow towards you. But doing this with your left hand...it woud be fubar. i.e. not correct.

but that is not my expertise.......and sometimes i'll just repeat what I hear

or is that threads........: )

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redfred
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#12

Re: thumb rule

12/04/2010 10:54 AM

The right hand rule is actually a mnemonic technique for the three dimensional vector calculation of a cross product. The study of magnetism is just typically the first field that one needs to apply this mathematic convention. Now there are times that you do use the left hand instead of the right, but always this is when some negation has occurred. In your example the current follows the direction of your right thumb in a conductor and the magnetic field lines wrap around the conductor in the direction of your fingers. But the actual flow of electrons in the wire is opposite the current flow convention. So if you point your left thumb in the direction of the electron flow, your left hand fingers will again show the direction of the magnetic field.

But to literally answer your question the choice to use the right hand as the standard instead of the left is just a firmly established convention. Just like the established convention that the Greek symbol Pi is the specific irrational number defined by the diameter and length of a perfect circle.

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malar
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#14
In reply to #12

Re: thumb rule

12/04/2010 10:57 AM

thank you i think i got my answer
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rhkramer
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#16

Re: thumb rule

12/04/2010 11:14 AM

I started to write an answer, but I think it would be easier (for me) and better for you to read something like http://en.wikipedia.org/wiki/Right-hand_rule--the Right-hand rule article on Wikipedia.

Most of it has to do with notation conventions chosen by men (not mother nature)--you, or someone, could choose to use a left hand rule, but then many of the signs (plus / minus) in various formulae would have to be reversed.
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lyn
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#17
In reply to #16

Re: thumb rule

12/04/2010 11:53 AM

The left hand rule is for motors.

I think Rule # 75 applies here, and to the other posts by malar.
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malar
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#18
In reply to #17

Re: thumb rule

12/04/2010 11:56 AM

please don't confuse right hand thumb rule with fleming's rule in generator and motor
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PWSlack
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#30
In reply to #18

Re: thumb rule

12/05/2010 3:06 AM

lynlynch isn't confused.

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#19

Re: thumb rule

12/04/2010 12:26 PM

You use the left hand when you are working on current flow and magnetism in positronic brains.
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Unredundant
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#20

Re: thumb rule

12/04/2010 12:38 PM
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lyn
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#21
In reply to #20

Re: thumb rule

12/04/2010 12:43 PM

And, since he has no shoes, there is no potential for electrons to flow through his body.

And, it is well known that blue has the highest insulating value of all the colors, so there's no spark jump to worry about from leaning over those live conductors.
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Gizma
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#22
In reply to #21

Re: thumb rule

12/04/2010 12:54 PM

No,use special electrical insulation shoe for your personal safety.
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Ragab1952
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#24
In reply to #22

Re: thumb rule

12/04/2010 2:01 PM

GA,but it is not complete, safety shoe alone in not enough, he should wear also safety helmet and safety elephant hose for his complete personal safety.
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lyn
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#25
In reply to #24

Re: thumb rule

12/04/2010 2:18 PM

Would that make it a GIA?
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Ragab1952
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#26
In reply to #25

Re: thumb rule

12/04/2010 2:44 PM

Sure,but if adds the face black mask.
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gringogreg
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#23

Re: thumb rule

12/04/2010 1:33 PM

"Right Hand Rule" for electrical engineers: Hold the light bulb in your right hand with your thumb pointing toward the screw base. Insert the bulb base into the socket and rotate it in the direction that your fingers are pointing. If you follow this rule, you will see the light. If you hold the bulb in your left hand it will fall on the floor and and break. Then you will forever be in the dark.

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klearzen
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#27

Re: thumb rule

12/04/2010 2:52 PM

Dear Malar, I will explain the reasoning behind the rule, if you can please help explain to my friend (from outer-space) which direction is Up.

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Hameedullah Ekhlas
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#29

Re: Thumb Rule

12/04/2010 10:50 PM

Just remember this

The right hand rule applies to the flows of positive charges. If negative changes are flowing, simply use your left hand.
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Users who posted comments:

Anonymous Poster (3); Gizma (1); gringogreg (1); Hameedullah Ekhlas (1); Hendrik (1); klearzen (1); lyn (8); malar (6); phoenix911 (2); PWSlack (1); Ragab1952 (2); redfred (1); rhkramer (1); Unredundant (1)

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