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doozy question in a paid for trial paper (1 Viewer)

Deus Ex Machina

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Howdy,
My physics trial today and I am frustrated with the exam paper and believe I recieved a doozy question. I know that not much is available on the age of silicon topic and that the people who write exams have to do research to write questions (I know it was a bought paper)... anyway here is the question... not exact words but like it...



Explain the optical non linearity property of silica, refer to CDs in your answer. 3 Marks.


I believe this is a doozy because the optical non linearity property refers to fibre optics which have nothing to do with CDs. Silica is not even used with CDs. Glass CDs, year right. They use a polycarbonate layer. CDs use optics, yes but not fibre optics.

You may have thought that well fibre optics is used in audio equipment, ie to transfer digital audio data from optical out to a reciever but this has nothing to do with CDs as it is a completly different technology (like talking about Aeroplanes when asked to talk about Monkeys - Aeroplanes sometimes carry monkeys but still its got nothing to do with the question)

Anyway I got home and did some research to find an answer and like I thought...nothing connected.


If you know how to answer this question or think its not a doozy or can point me in the right direction.. pls do so.
 

phizz

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Explain the optical non linearity property of silica, refer to CDs in your answer. 3 Marks.

To my knowledge CDs are made from polycarbonate, and not silica. However the question may want you to explain optical non-linearity properties of silica, with the support of the non linearity property of CDs. It could be about the Interference colors and Iridescent reflections on the disc maybe?

But if this is the case, then this question is a bit silly as it requires you to know something outside of the sylabus. If questions were like this, then you would be required to know the optical non-linearity of everything!

Either way, its not the clearest of questions
 
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Äj

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OK, you wont get a question like that...sorry, WE wont get a question like that.(whole state gets same qns)
that question is complete bull crap, has nothing to do with the sylibus and doesnt even make propper sense.
cds dont have anything to do with optical nonlinearity as they are pretty much reading a brail form of morse code on a cd. (just reading either shorter pits for 0's, or longer ones for 1's).

the laser has to go through the plastic first but it is focused on the metallic layer on the other side, not the plastic itself, so there is very little the plastic does to the laser.

this question isnt even remotely worth worrying about. they WILL NOT give us a question like this, i guarantee it.

if all else fails, its only a 3 marker. not big deal, just try n BS it if you can be bothered. im like age of silicon god and i wouldnt wory. lol

but seriously, dont even wory about something like this. its way outside the sylibus and doesnt even make sense. just make sure you know the sylibus well and youll be fine. and if you want to do really well make sure you do extra research on core ideas and topics so you really know them. as opposed to doing what most do and just regurgitate the text book. :D
hope this helps
 

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