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    Why does the core need to have a higher refractive index (more dense) than the cladding in order for light to travel down the fibre in a series of total internal reflections? what is the reason for this structure?
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    I haven't done this for about a year so I cant remember the details (or any of the equations) but..

    the general reason is..

    If the cladding has a lower refractive index than the core, the angle at which it reflects will always be lower than the critical angle (I cant remember why). This ensures that no light is refracted out of the core and results in TIR.

    That's about as much as I can remember Im afraid. Theres probably loads of info around online, you just gotta search.

    This is one reason but im not sure if its what you want:

    When a light ray/signal is refracted a lot within the fibre, it can become dispersed and so the data it carries can become messy. The ray disperses due to different possible paths it can take within the fibre, and as some paths are longer than others, differnt parts of the signal can reach the end of the wire at slightly different times. The different materials allow the signals to travel faster when it is at the edges of the fibre, and slower when its nearer the middle. This compensates for the different path lengths.
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    please don't answer any of his questions
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    (Original post by DanMushMan)
    please don't answer any of his questions
    It was a sensible question? You shouldn't always ignore a post just because of the poster's reputation...
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    I reckon anybody who wastes their time helping him is doing themselves a disservice and should be informed as such. But maybe that's because I'm a cold hearted *******, who knows really...
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    (Original post by kildare)
    I reckon anybody who wastes their time helping him is doing themselves a disservice and should be informed as such. But maybe that's because I'm a cold hearted *******s, who knows...
    its not just about helping him, because other people with the same query might come on here and do a search and get the answer
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    (Original post by elpaw)
    its not just about helping him, because other people with the same query might come on here and do a search and get the answer
    Hmm fair enough, I reckon anybody who came on here to ask that specific question would be almost guaranteed to post a new thread about it but how and ever.

    whats wrong with answering the question?
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    (Original post by Adhsur)
    It was a sensible question? You shouldn't always ignore a post just because of the poster's reputation...
    k ,last time people answered a question, he then posted something along the lines of: 'ha ha you fuking idiots. i knew the fuking answer all along and was just wasting your f-ing time. ha ha' or something like that.
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    He's never done anything wrong towards me, but maybe thats cos I havent been on here in about 6 weeks..

    Ill wait til he does and make my own decision, but thanks for the thought.
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    He's banned now anyway as far as I know.
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    (Original post by Petrozzi)
    He's banned now anyway as far as I know.
    I think he also registered today as Maskhound, and got banned again.
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    (Original post by Chicken)
    I think he also registered today as Maskhound, and got banned again.
    Maybe the mods or d should just report him to his isp..?
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    (Original post by Chris_)
    Maybe the mods or d should just report him to his isp..?
    Hmmm maybe...anyways how are you? Still having fun?
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    (Original post by Chris_)
    Maybe the mods or d should just report him to his isp..?
    already been done to no avail
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    (Original post by Chicken)
    Hmmm maybe...anyways how are you? Still having fun?
    Sure am, jus got back from the bar. I cant get on msn right now though, the network has been so bad again all day..

    and u?
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    (Original post by Chris_)
    Sure am, jus got back from the bar. I cant get on msn right now though, the network has been so bad again all day..

    and u?
    Still good - my network has been fine all day?! We just had Indian takeaway and I feel really stuffed!!! I have 2 lab reports to hand in tmw yet I haven't done either and I'm still online...!!!!
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    (Original post by elpaw)
    already been done to no avail
    ok, why doesnt everyone just ignore him then. In another thread today one of the mods actually provoked him, seems a bit stupid to me.
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    (Original post by Chicken)
    Still good - my network has been fine all day?! We just had Indian takeaway and I feel really stuffed!!! I have 2 lab reports to hand in tmw yet I haven't done either and I'm still online...!!!!
    Pah welcome to my world, I have stuff to do too. Is there any cure for procrastination?
 
 
 

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