Current generated by plasma of uneven density in a Magnetic Field

AI Thread Summary
The discussion focuses on understanding the behavior of plasma in a magnetic field, particularly regarding the upward motion of ions and the flow of electrons. The upward motion is clarified as a result of velocity parallel to the magnetic field, allowing for helical movement. There is confusion about how plasma pressure arises and its implications for ion and electron movement. The courteous nature of the question posed is noted, highlighting a positive aspect of the inquiry. Overall, the thread emphasizes the complexities of plasma dynamics in magnetic fields.
phantomvommand
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Homework Statement
Please see the attached photo.
Relevant Equations
NA, this is a qualitative question.
I am only asking about part (b)(i) and (b)(ii).

IMG_6756.jpg

Below is the explanation for (b)(i).

IMG_6757.jpg

What is going on in the above? I understand up till the 3rd line, about the left/right hand circular motion. What is the "upward motion" the solution mentioned? Is it suggesting that ions are moving upwards, as indicated by the purple arrow J? If so, how is that happening; since pressure is in the X, not Y direction? Furthermore, why would electrons flow in the opposite direction as ions? I think I am unclear about how this "plasma pressure" arises, and thus unaware of its effects.

All help is appreciated.
 
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I have since figured this out. I think The question means that there is a velocity parallel to the magnetic field too, hence allowing for an upward/ downward helical movement.
 
I'm very impressed by the courtesy of the person who wrote the questions. I can't remember seeing 'please' being consistently (or ever!) used in physics questions.
 
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