Reception of distant FM radio broadcasts

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The discussion addresses the reception of distant FM radio broadcasts, noting that unlike AM signals, FM reception does not improve after nightfall. Participants suggest that AM signals benefit from reflection by the ionosphere, which is more effective in darkness. There is also a query about determining the charge distribution on an airplane's wings due to its motion in a magnetic field, with references to using the right-hand rule for direction of force on charges. The conversation highlights curiosity about the effects of solar ultraviolet radiation on the ionosphere. Overall, the differences in signal behavior between AM and FM broadcasts are central to the discussion.
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1. An aluminum airplane is flying west, parallel to the ground, at 350 m/s. The Earth's magnetic field produces a downward component of 8.30 x10-5 T at that point. For the purposes of this question, treat the wing as if it was a conducting rod.
a) What is the magnitude of the potential difference applied across the plane's wingspan of 22 m?

I used V=LvB, and got an answer of 0.64 V.

b) Which wing would be negatively charged, the one on the south side of the plane of the one on the north side of the plane?
This is where I'm lost. How would I find out the answer to this?



2. Why doesn't the reception of distant FM radio broadcasts improve just after night fall the way AM broadcasts do?
I'm assuming AM signals improve because they are reflected by the ionosphere, which would be higher in the dark? That could be WAY off.
 
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a) for me ok too
b) how do you find the direction of force to the charge which move in magnetic field?
 
...Oh, do I use the left hand rule? Haha.
 
heh...for (b), you could use the right hand rule (or left hand version as well).
For (c)...interesting question...not sure.
 
the (c) part is a good question and am curious this too, even didn't noticed this :) BTW, you may research the effects of ultraviolet beams of sun on ionospher. I found something from google. You are close.
 
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