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Multi choice Q15 (1 Viewer)

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Wondering what people got and why, seemed like the only hard multi choice to me.

"a block of silicon dope with boron is connected as shown in the diagram below"

i guess that we will all agree they move left, but was it the conduction band or valance band?

zzz i was gonna make it a poll but, "You can only add a poll to a thread within 2 minutes of posting the thread." :(
 
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alez

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i think i put conduction band electrons go to the left, iirc
 

Aaron.Judd

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They move left. I put d, conduction band. Most peopel at my centre put d.
 

Jaspal

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alez said:
i think i put conduction band electrons go to the left, iirc
Yeah i think i did that as well. I forget, that question i didn't really get.
 

alez

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dolbinau said:
Alex, I also put that. 15 (d), woot.
sweeeet. bit of a guess
what did you all get for the forces acting on the satellite? forget which number it is
 

proringz

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So it's doped with Boron, making it a p-type transistor so therefore the answer is.... that's about as far as I got.
 

dolbinau

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C) (Gravity is the only force acting on the satellite and this results in an inward acceleration).

But what about 5? I might need to start a new topic, the one about the clock - I wasn't sure about that. Was it 0.63 seconds?
 

Arithela

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i got B as the VALENCE BAND electrons move into the conduction band in order to conduct
 

proringz

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Arithela said:
i got B as the VALENCE BAND electrons move into the conduction band in order to conduct
I got A, as it goes from positive to negative terminal. I'm not really sure to be honest.
 
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yeh i put d initially then changed it to b.
it is a p type conductor so the holes are in the valance band. Thus the electrons rather strangly travel through the valance band in order to conduct.
 

Arithela

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proringz said:
I got A, as it goes from positive to negative terminal. I'm not really sure to be honest.
im pretty sure electrons are attracted to the positive terminal, i.e. to the left
 

crestor

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dolbinau said:
C) (Gravity is the only force acting on the satellite and this results in an inward acceleration).

But what about 5? I might need to start a new topic, the one about the clock - I wasn't sure about that. Was it 0.63 seconds?
Thats what I got, if i changed the To and Tv around i could get either 0.40 or 0.63 but i reasoned that it would have to be bigger/longer
 

timmiitippii

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i got electrons move left in valence band...
becoz p-type has holes and holes moves in opposite directions to electrons and holes are in the valence band...
and since it was negative terminal on the right and electrons flows from neg to pos, then that's why i chose left with valence..
i'm not sure if i'm right. :uhoh:
 

JamesTockuss

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If you used the time dialation formula for 5 you got (c), but since the ship is moving away at a constant speed it's gunna take extra time for the signal to get to earth - so the answer had to be (d)
 

proringz

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Arithela said:
im pretty sure electrons are attracted to the positive terminal, i.e. to the left
Ahh, but I think that is the direction of conventional current. If it says which way conduction occurs, like the question said, it's from positive to negative.
JamesTockuss said:
If you used the time dialation formula for 5 you got (c), but since the ship is moving away at a constant speed it's gunna take extra time for the signal to get to earth - so the answer had to be (d)
But the time interval measured (0.5s), I assume, would have already included the extra time for the signal to reach earth.

I uploaded for those who don't have the paper:
http://img266.imageshack.us/my.php?image=q15xi7.jpg
 
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Aaron.Judd

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JamesTockuss said:
If you used the time dialation formula for 5 you got (c), but since the ship is moving away at a constant speed it's gunna take extra time for the signal to get to earth - so the answer had to be (d)
I disagree. Fairly sure it is c.
 
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proringz said:
I got A, as it goes from positive to negative terminal. I'm not really sure to be honest.
well i got a too, which was a guess, because i had no idea. i can never remember which terminal is which :(

but seeing how most people have put d, i was wrong in every way.
 

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