Why do we use a different right hand rule for solenoids?

[hellocubed]

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I was wondering why exactly we use the second right hand rule for the solenoid. why is the first right hand rule no longer applicable?

 

[pfaction]

You do use RHR for solenoid. It's just in a different kind of plane. When you're talking about a moving charge that feels a force due to a field, you use the RHR. When you're talking about the current creating a field like in a solenoid, it kind of curls around.

 

[hellocubed]

yes, it is the right hand rule. But just as you mentioned, there are two variations that deal with two planes.

I don't really understand how one relates to the other
http://www.diracdelta.co.uk/science/source/f/l/flemings right hand rule/image001.jpg

http://4.bp.blogspot.com/-8e_cyTZXH...Y/WQDcj4Ynna8/s400/Right-Hand-Grip-Rules2.png


Basically, Why does the rule curl to the left? (if it curled to the right then the induced emf would point the other direction)

 

[pfaction]

Use your thumb to point conventional current in the same direction as the arrows of the 2nd picture at the south side. Curl your fingers. Shift your hand over and realize it's the same for the north side! You're using the same rule. And yes, if it were wrapped the other way, I think it would be the opposite--you've just flipped the solenoid over, though.

 

[hellocubed]

Use your thumb to point conventional current in the same direction as the arrows of the 2nd picture at the south side. Curl your fingers. Shift your hand over and realize it's the same for the north side! You're using the same rule. And yes, if it were wrapped the other way, I think it would be the opposite--you've just flipped the solenoid over, though.

yes I am aware of how to use it.

I am asking why it contours to your hand in the first place? Why does an induced emf point to the north when the current flows clockwise?

What force is altering the first RHR to result in the contouring of the second RHR?