Magnetism right hand rule question

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fritolays08

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Hello. Can somebody please explain this question to me? I am completely lost.

A high current power line is supported 10 m above ground and carries a current from West to East. A negatively charged balloon is released directly below the power line and begins to float straight up toward it. What is the direction of the magnetic force on the balloon due to the magnetic field surrounding the power line?

(A) North
(B) South
(C) East
(D) West

I get that when you point your right thumb in the direction of the current and curl your fingers, at the bottom of the wire the magnetic field points up (north). However, when I do the rule to find the magnetic force on the balloon I get the force coming out of the page? The answer is east, but I'm confused as to how that is. Any help with my reasoning with this would be appreciated.

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Okay, so first you need to figure out which direction the magnetic field due to the wire points. We can ignore the balloon for now.

PUFYzBt.png


As shown here, if the current is traveling to the right (east), then the magnetic field is out of the page above the wire and into the page below the wire, due to the right hand rule.

Now that we know that the magnetic field below the wire (where the balloon is) points into the page, we can consider just the balloon as a point charge moving in a magnetic field.

KfV1h8G.png


Here, you can see that v points up and B is into the page. We know F = q (v x B). The cross product of v x B points to the left (west), but because the balloon is negatively charged, the force on the balloon is to the right (east).
 
Fleming's right hand rule is not applicable in this situation. Use Flemings left hand rule. Right hand rule is to find the direction of induced current (electromagnetic induction) on a conductor moving in an external magnetic field. Left hand rule is for finding the direction of force on a charged particle or, direction of force on a charge carrying conductor like wire when it is placed in an external magnetic field. Two very different scenarios.....

I know this can sound very confusing and I had to muddle through it as well. TBR and Kaplan (that I have) don't mention Fleming's rule at all, and neither the topic of electromagnetic induction. They mention a right hand rule which I find confusing. But after breaking my head over it many times and researching on the internet, I found that there are basically 3 rules you need to remember, Flemings left hand rule is for (motors which rotates does work, force on a charge particle etc.) and Flemings right hand rule is for (generators, generates current i.e., induced current), and Maxwell cork screw rule. That is it, I think.
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Sorry.........ignore what I wrote above. I thought you mentioned Flemings right hand rule, but you mentioned right hand rule.......so I am guessing it is the same right hand rule that those books mention, which I find confusing.......
 
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