Right Hand Rule for Electromagnets

AI Thread Summary
The discussion centers on understanding the right hand rule in relation to electromagnets, particularly how the direction of current flow affects magnetic polarity. A diagram was created to visualize the flow of electrons and magnetic poles, but it was noted that the winding direction of the wire is crucial for determining magnetic polarity. It was clarified that the right hand rule applies to conventional current flow, which is opposite to electron flow, leading to confusion for the original poster. The participants emphasized that the battery polarity must be reversed to align with the magnetic field direction shown in the diagram. Overall, the right hand rule is essential for correctly interpreting the behavior of electromagnets.
N-SKY
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Ok I’m trying to understand the right hand rule in relation to electromagnets. Since I’m a visual learner I made myself a little diagram. Is my little diagram correctly showing the flow of electrons relative to the magnetic poles?
Also does the core and helix being slightly curved affect the lines of magnetic force as opposed to the core being straight?
eMAG_s.png
 
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N-SKY said:
Ok I’m trying to understand the right hand rule in relation to electromagnets. Since I’m a visual learner I made myself a little diagram. Is my little diagram correctly showing the flow of electrons relative to the magnetic poles?
Also does the core and helix being slightly curved affect the lines of magnetic force as opposed to the core being straight?
View attachment 276265
It's not clear from the drawing whether the winding around the core is left handed or right handed. In other words, is the winding such that the wire leaving the positive terminal is wrapped from the front of the core towards the back or the other way around?
 
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is the winding such that the wire leaving the positive terminal is wrapped from the front of the core towards the back or the other way around?

Hey thanks for the reply.

From my basic understanding the wrapping of the wire is not that important. It is the direction of the electric flow, no?

In my image the wire leaving the positive terminal is connected to the “north” side.

But here is a side view of the wrapping. Hope that’s more clear.

side_view.jpg
 
Inductor-magnetic-field.jpg


With N on the left, S on the right end of the coil

Note it is showing conventional current, not electron flow

so that makes your diagram incorrect :wink: That is, to satisfy your magnetic polarity, your battery polarity needs to be reversed

(Electron flow will be IN on the Nth end of the coil and OUT on the Sth end of the coilDave
 
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As @davenn already noted, to get the field lines pointing as shown in post #1, the battery must be connected as shown below. Current flow is conventionally opposite to electron flow, from positve battery terminal to negative. If you wrap the fingers of your right hand in the direction of the current, you thumb will point to the left which means that the field lines will come out the "N" side, loop around and go into the "S" side.

Coil.png
 
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And of course the Magnetic Field lines do not directly indicate the force on a charge but requires another exercise of the right hand rule.
 
hutchphd said:
And of course the Magnetic Field lines do not directly indicate the force on a charge but requires another exercise of the right hand rule.
... if the charge is moving.
 
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...Note it is showing conventional current, not electron flow

...Current flow is conventionally opposite to electron flow

Ahh ok. So the right hand rule works with conventional current direction and not the electron flow direction. I think that’s what was confusing me.

Thanks for the help guys.
 
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N-SKY said:
So the right hand rule works with conventional current direction and not the electron flow direction.
Note that the left hand gives the negated result of the right hand.
 
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