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

  • #1
Daniel2244
125
5

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
Science Advisor
Homework Helper
Insights Author
Gold Member
38,457
7,967
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
Daniel2244
125
5
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
Science Advisor
Homework Helper
Insights Author
Gold Member
38,457
7,967
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
Daniel2244
125
5
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
Science Advisor
Homework Helper
Insights Author
Gold Member
38,457
7,967
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
Daniel2244
125
5
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
Daniel2244
125
5
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
Science Advisor
Homework Helper
Insights Author
Gold Member
38,457
7,967
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.
 

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

Replies
12
Views
428
  • Last Post
Replies
5
Views
358
  • Last Post
Replies
7
Views
308
  • Last Post
Replies
3
Views
402
Replies
2
Views
682
  • Last Post
Replies
5
Views
903
Replies
7
Views
2K
  • Last Post
Replies
4
Views
1K
Replies
5
Views
2K
Top