Recent content by ryan750

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    The Susskind Counter Information Paradox?

    it sounds like u think uve got sumthing to blow the minds of the scientific community with. I guess i believe the same with my theories and mine predict that information isn't lost. It is awfully simple but wil keep tight lipped till more thinking has been dun
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    Photon, Gravity, Mass and Black Holes.

    my astronomy teacher said that black holes have zero volume and infinite density. Also he said they all have fixed mass. i really don't get the first two and personally don't think this is true.
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    How do I solve INT x sec^2x dx using integration by parts?

    show that INT x sec^2x dx = pi/4 - ln2/2 (between pi/4 and 0) pls help i don't know where to start i know it is integration by parts - just don't know how i should rearrange it. thanks
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    Xn+1 = Xn(2 - NXn) can be used to find the reciprocal

    Xn+1 = Xn(2 - NXn) => (Xn+1)/Xn = 2 - NXn => NXn = 2 - (Xn+1)/Xn => NXn = (2Xn -Xn+1)/Xn => N = (2Xn - Xn+1)/(Xn)^2 => N ~= Xn/(Xn)^2 => N ~= 1/Xn Which is a good estimate for the recipricol. I found sum1 that could do it. i didn't think about just rearranging the formula.
  5. R

    Xn+1 = Xn(2 - NXn) can be used to find the reciprocal

    it works for all values of N and u can use any value of Xn - but u would preferably choose a number that is royughly 1/n. So if N was 7 u would use 0.1. If n was 53 u would use 0.02.
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    Xn+1 = Xn(2 - NXn) can be used to find the reciprocal

    can any1 explain why this iteration: Xn+1 = Xn(2 - NXn) can be used to find the reciprocal of N. I don't ned proof or to show that it does but i would like to know if sum1 can break it down and explain how it does it.
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    Understanding the Mechanics of Light-Induced Voltage in L.E.D.s

    so the light provides the energy to valence electrons in the n type to be excited and they are attracted to the p type and combine with holes. This process carried out produces energy changes to the electrons and holes which creates the potential difference seen. is this right?
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    Understanding the Mechanics of Light-Induced Voltage in L.E.D.s

    sorry - so electrons from type move top n tyoe and holes move from n tyoe to p type. can i just ask what holes are? i know they are positive but that's it.
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    Understanding the Mechanics of Light-Induced Voltage in L.E.D.s

    ok - i just need yto clear this subject up once and for all - the l.e.d has no power supply - just a voltmeter to take readings with. so if there was no power supply why would the electrons move from the p - type material to the n - type material when this type is more negative right. As...
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    Understanding the Mechanics of Light-Induced Voltage in L.E.D.s

    okay so no relaxation either - man - all of my course terminology has gone so out of the window - but I am glad that I am going to get it right. and thankyou for welcoming me - i can't wait to get stuck into all of these rooms and all of the interesting topics out there.
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    Understanding the Mechanics of Light-Induced Voltage in L.E.D.s

    also last thing - the potential difference occurs in the l.e.d because of the energy changes to the electrons. The electrons move from higher to lower and from lower to higher levels - so these energy changes are the potential difference in the l.e.d. i know that's basic stuff but i just want...
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    Understanding the Mechanics of Light-Induced Voltage in L.E.D.s

    oh yes and jus to clear up - when the valence electron moves thru the conduction band to fill the positive holes in the valence band of the p - type semiconductor - the excited electron relaxes and emits light yes.
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    Understanding the Mechanics of Light-Induced Voltage in L.E.D.s

    right i really think I've got it now - thanks for persevering with me - i probably would have lostthe marks in the exam if i had said it was due to the photoelectric effect - I am so glad i have researched it now. oh and sorry for doubting u guys - i had no idea that u were expert in the subject...
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    Understanding the Mechanics of Light-Induced Voltage in L.E.D.s

    its ok i have just emailed a source that is expert on the subject - it is a diode company and they should be able to explain all - thanks for all ur help
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    Understanding the Mechanics of Light-Induced Voltage in L.E.D.s

    ok - u seemed pretty clued up about this subject: please could u give a concise account to this question - it would be greatly appreciated - even if it means repeating some of the details that have been said on this thread already - pls: Light from a filament lamp is incident on a l.e.d that...
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