Direction of the magnetic force

AI Thread Summary
The discussion revolves around the confusion regarding the application of the right-hand rule for determining the direction of the magnetic force in a current-carrying conductor. The original poster mistakenly used the left-hand rule, leading to an incorrect answer. Clarification was provided that the right-hand rule should be used for current, as it flows opposite to the direction of electron movement. The key point of contention is understanding why the answer is A when following the correct application of the right-hand rule. The conversation emphasizes the importance of correctly identifying the thumb, fingers, and palm orientation in relation to the magnetic field and current direction.
Nitrate
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Homework Statement


The problem is in the attached image.


Homework Equations





The Attempt at a Solution


I used the third left hand rule (seen in one of the attached images) and pointed my thumb (direction of the current) downwards because the question states that the current flows from point E to point F. However, when I point my thumb downwards I seem to get B as the answer... and my answer key says that A is the answer. I need a bit of clarification please (a drawing might be helpful.)
 

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Hi Nitrate! :smile:
Nitrate said:
I used the third left hand rule …

No, for current, it's the right-hand rule. :wink:

(It's only the left-hand rule for electrons, because the current is defined as going the opposite way to the electrons)
 
tiny-tim said:
Hi Nitrate! :smile:


No, for current, it's the right-hand rule. :wink:

(It's only the left-hand rule for electrons, because the current is defined as going the opposite way to the electrons)

My mistake. That being said, I still don't understand why A is the answer.
 
Hi Nitrate! :smile:
Nitrate said:
… when I point my thumb downwards I seem to get B as the answer …
Nitrate said:
… I still don't understand why A is the answer.

I don't get it :confused:

if your right thumb is down, and your fingers are pointing along the field (from N to S, ie from C to D),

then isn't your palm is pointing towards you, ie towards A ?​
 
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