03 March 2006

Topic open: Magnetic fields

The following topic is now open for questions: Magnetic fields.

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1 comment:

Anonymous said...

I would like to have clarified a number of points regarding the Magnetism slides.

1) Regarding B and decrease of B as distance from I increases.

The relationship between B and distance from I (r) is B ~ 1/r (re: Capa 8 q 1a). However, in the class slides (slide 1 p. 4) it says

" delta B ~ 1/r2 (r squared)"

What r is this? I notice this is not the perpendicular r, but in the following delta B equation, sin theta is multiplied, and thus becomes the perpendicular r. Confusion?

2) Slide 2 p. 5, for a circular clockwise I, P1 within the circle points into the page, while P2 outside the circle points out of the page. Is it that B's outside a circular I are always in the opposite direction as that in the I?

3) slide 4 p. 3. The current loops in the diagram show a B opposite to RHR. Is it because the loops are electron orbitals, and electrons produce B's opposite to RHR?

4) similar question as previous. slide 1 p. 6. why is the B opposite to the RHR?

Thank you.