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Old 14th May 2002 | 10:39
  #12 (permalink)  
Token Bird
 
Joined: Dec 2000
Posts: 274
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From: Warks
omh,

Wow, you're smug aren't you.

For one thing, I am not struggling (unless you consider a 90% average to be evidence of me struggling). For another thing, just because I did not quote the bit of the notes that said that the sensitive axis and the spin axis were the same thing, does not mean that it did not say it. I just didn't happen to quote that bit.

You said:
No, they say that the sensitive axis will produce a precession in response to rotation about it. Says nothing about the spin axis.
No you're right, it doesn't say anything about the spin axis in that particular sentence. Sorry for failing to quote the entire book. I'll know better next time. Unless of course you have read all my notes and know for sure that they did not say anywhere that the sensitive axis and the spin axis are the same thing.

When I posted the original quote, I made the fundamental assumption that the spin axis and the sensitive axis were the same and thought you would all also assume it, since I had read it elsewhere in my notes. It was only later that it came to light that they were different, which put the section I quoted in a completely different context and it would therefore be correct. However, the other part of the notes which stated that the spin axis and the sensitive axis are the same, must therefore be incorrect. They cannot both be correct. Do I have to explain this any more times or has it sunk in yet?

For your information, apparently the previous set of students on this course (none of whom were struggling either, judging from their results) had exactly the same argument about the same question. It even foiled the instructor, all because of this mistaken assumption that the spin axis and the sensitive axis were the same thing. Considering that 1 instructor and 18 student all made the same mistake, I think it damn good evidence that we were taught something in error, unless of course we are all struggling and all trying to blame our notes, including the instructor,

TB

PS. Almost forgot - I think I did already mention in one of my above posts that I got the question right, therefore the argument that I am trying to 'blame' someone else for something makes no sense. The point was that the question caused a big uproar in class, hence I decided to come onto PPRuNe to see if I could get some clarification. Thank you to those of you who did actually make useful comments, the mystery is now solved, but I will think twice about asking any technical questions on this forum again since some people like to use this as an excuse to accuse other people of being dense

PS2. TBL - my classmates liked your aide memoire with the bed. Thanks

PS3. I shared the above information with my instructor, who also agrees that the notes were incorrect. Needless to say I have erased the offending line from my notes

Last edited by Token Bird; 14th May 2002 at 15:42.
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