Fleming's left and right hand rule - how do they work?

  • #1
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Homework Statement


AC production and relationships that determine movement and current flow direction from Flaming's left hand and right hand rule.

Homework Equations




The Attempt at a Solution


Left hand rule for motors- right hand rule for generators
The thumb, index and midle fingers are all right angles to each other.
For left hand rule: I use FBI - thumb = direction of force, index finger = magnetic field and middle finger = direction of current flow.
For right hand rule: I used FBI - thumb= direction of applied force, index finger = direction of magnetic field and middle finger = direction of induced current
AC would use Fleming's right hand rule because a current is induced as well as being produced by a generator.

Just very comfusing as I have come across videos saying that the two fingers are the opposite way around for right hand rule
 

Answers and Replies

  • #2
haruspex
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On a quick search, I have not found any references that swap the fingers in the way you mention. Please post a link to an example or two.
 
  • #3
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On a quick search, I have not found any references that swap the fingers in the way you mention. Please post a link to an example or two.
They're videos: and I can't find the other one.
 
  • #4
haruspex
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They're videos: and I can't find the other one.
Ok.
The video provides a right hand rule applicable to a motor. You are used to using a left hand rule for motors, hence the need to swap the fingers. Confusing, but correct.
 
  • #5
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Ok.
The video provides a right hand rule applicable to a motor. You are used to using a left hand rule for motors, hence the need to swap the fingers. Confusing, but correct.
Thanks for clearing it up for me :) I tried looking in comments for reason he did it like but only found poeple with the same question. Also would the right hand rule be applied to the AC production? I would think so just want to double check.
 
  • #6
haruspex
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would the right hand rule be applied to the AC production?
The right hand rule in the form you are familiar with applies to a generator, yes.
To get the rule for a motor you either swap hands or swap fingers.
 
  • #7
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The right hand rule in the form you are familiar with applies to a generator, yes.
To get the rule for a motor you either swap hands or swap fingers.
Ok thanks
 
  • #8
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Ok thanks
Not to nag but if current flows away from you and the magnetic field is towards the right the the direction of force is up but when the current/voltage changes polarity and becomes negative would the direction of force be down
 
  • #9
haruspex
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Not to nag but if current flows away from you and the magnetic field is towards the right the the direction of force is up but when the current/voltage changes polarity and becomes negative would the direction of force be down
Yes.
 

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