Five Hand Rule: Identifying Wire Direction

In summary, the conversation discusses the use of the left hand rule and right hand rule in determining the direction of the force on a current-carrying wire in a magnetic field. The right hand rule is recommended for this purpose, with the thumb representing the direction of the cross product. There is also mention of the "hand rule" and the "screwdriver rule" as alternative methods for determining direction. The conversation also touches on the different driving sides in the UK and US and the potential connection to the hand rule.
  • #1
valerie001
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What is the five hand rule?


I need to know what direction the wire is going to move

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  • #2
Do you mean Left hand rule and right hand rule by any chance?

Wire direction in a magnetic field is given by the Left hand rule.
First finger = field direction
Second finger = current direction
Thumb = force direction.

Make all three fingers perpendicular to each other. If you can't see how to do this, watch an Eminem video!
 
  • #3
right hand rule

I recommend that you learn to use the right hand rule to find the force on a current-carrying wire in a magnetic field.

Here are two links that may help with the right hand rule:
http://www.physics.brocku.ca/faculty/sternin/120/slides/rh-rule.html
http://physics.syr.edu/courses/video/RightHandRule/

(Sorry, but I don't think that's Eminem doing the demos in the second link. :smile: )
 
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  • #4
Doc Al said:
I recommend that you learn to use the right hand rule to find the force on a current-carrying wire in a magnetic field.

Right hand rule?? Don't you mean left hand rule, or do we do this different in the UK?

Left hand rule gives direction of the force on a wire in a magnetic field where the current direction is CONVENTIONAL current flow, not electron flow.

In the case above, the wire moves OUT of the PC screen towards you.
 
  • #5
Adrian Baker said:
Right hand rule?? Don't you mean left hand rule, or do we do this different in the UK?
Looks like you do it differently. (I'm willing to use [itex]f[/itex] instead of [itex]\nu[/itex] for frequency, but don't mess with my right hand rule! :smile: )
Left hand rule gives direction of the force on a wire in a magnetic field where the current direction is CONVENTIONAL current flow, not electron flow.
So does the right hand rule. I use the right hand rule whenever a cross product is involved. To find the direction of [itex]\vec{A}\times\vec{B}[/itex], just curl the fingers of the right hand from A to B along the shortest arc. The thumb points in the direction of the cross product. (At least that's the way I do it. Check the second of the links I posted for live action video of the right hand rule in use.)

In the case above, the wire moves OUT of the PC screen towards you.
Apparently the right hand rule and your left hand rule give the same answer. Good thing, I suppose!
 
  • #6
The left hand and right hand rules are both taught in my school. We are taught to use the right hand rule for finding the directions of protons and the left hand rule for electrons (since the directions are opposite). However, the right hand rule is used primarily since the direction of the curled finger can just be made opposite if the particle is negative and the direction left the same if the particle is positive. They're interchangable methods, just depends on your preference. Here in the US it's standard to use the right hand, however.
 
  • #7
z-component said:
The left hand and right hand rules are both taught in my school.
Again, a deficit of having never finished high school. I was taught only the left-hand rule. (ie: thumb in direction of current flow puts fingers in direction of magnetic field and vice versa) Jeez, but I love learning new stuff here!
 
  • #8
This is the LH Rule as we teach it:
 

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  • #9
Could there be some mysterious connection between the "handrule" and which side of the road you drive on? :biggrin:
 
  • #10
No it doesnt, in the UK we drive on the correct side of the road, whilst you americans drive on the other side just because its the opposite of the english (do to the revolution etc...)
 
  • #11
AcEY said:
No it doesnt, in the UK we drive on the correct side of the road, whilst you americans drive on the other side just because its the opposite of the english (do to the revolution etc...)

Well, that's exactly my "theory" you see...
(left hand side-left hand rule,
right hand side-right hand rule)

Anyway, I thought it was well-known Sweden is not one of the United States of america. :wink:
 
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  • #12
theres the all new (?) screwdriver rule for everyone that gets confused as to which hand is the right one. its the same basic idea, i.e. the thumb and fingers only point in one direction, instead of hand curling somewhere is which way you turn the screwdriver and the thumb direction is analogous to which way the screw you are screwing would go under that kind of rotation.

this is really a difficult explanation of something very simple. and actually clockwise and c-clockwise is inherent if you want to know which way the screw goes, so you don't need to make funny hand symbols as you do it.

oh and this ties in nicely with right tighty - lefty loosey ;)
 
  • #13
T@P said:
this is really a difficult explanation of something very simple. and actually clockwise and c-clockwise is inherent if you want to know which way the screw goes, so you don't need to make funny hand symbols as you do it.

oh and this ties in nicely with right tighty - lefty loosey ;)
That works fine until you run into a left-hand thread and strip the thing.
 
  • #14
Clockwise is confusing too - if you are the clock!

To a clock the hands go anti-clockwise.
 
  • #15
Adrian Baker said:
Clockwise is confusing too - if you are the clock!

To a clock the hands go anti-clockwise.
Not if it's dyslexic.
 

FAQ: Five Hand Rule: Identifying Wire Direction

What is the Five Hand Rule?

The Five Hand Rule is a simple and effective method used to identify the direction of current flow in a wire. It involves using five fingers of your hand to represent the five main components of a circuit: power source, load, switch, ground, and wire.

How does the Five Hand Rule work?

To use the Five Hand Rule, hold out your hand with your four fingers pointing in the direction of the flow of current (from positive to negative) and your thumb pointing in the direction of conventional current flow (from negative to positive). The palm of your hand represents the wire, with the thumb acting as the positive end and the fingers as the negative end.

What is the purpose of using the Five Hand Rule?

The Five Hand Rule is used to quickly and easily determine the direction of current flow in a wire. This information is important in troubleshooting circuits and understanding how different components are connected in an electrical system.

Can the Five Hand Rule be used for all types of circuits?

Yes, the Five Hand Rule can be used for all types of circuits, including DC (direct current) and AC (alternating current) circuits. It is a universal method that applies to any type of electrical system.

Are there any limitations to using the Five Hand Rule?

The Five Hand Rule is a simple and general method that may not be accurate in certain situations, such as when dealing with complex circuits or circuits with multiple power sources. In these cases, more advanced techniques and tools may be necessary to accurately determine wire direction.

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