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    (Original post by Mutleybm1996)
    which paper?
    how are you feeling about this exam?
    any advice/tips?
    June 2014.

    Confident.

    Advice/tips - remember the three points for all wordy BF questions and, actually, for all the energy/speed/ideal gas wordy questions - there will always be at least 1.
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    Been getting ~80% in past papers 2006-2014, but I know OCR will have something nasty in store for tomorrow so >_>
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    (Original post by DomStaff)
    June 2014.

    Confident.

    Advice/tips - remember the three points for all wordy BF questions and, actually, for all the energy/speed/ideal gas wordy questions - there will always be at least 1.
    what are the "three points"?
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    (Original post by DomStaff)
    June 2014.

    Confident.

    Advice/tips - remember the three points for all wordy BF questions and, actually, for all the energy/speed/ideal gas wordy questions - there will always be at least 1.
    what's 1/e? what's e?
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    (Original post by Mutleybm1996)
    what's 1/e? what's e?
    e is the base of the natural logarithm.
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    (Original post by Mutleybm1996)
    what's 1/e? what's e?
    1/e is about 0.37. So basically you can say that the time constant is the time taken for the current to fall to 37% of its initial value. e is just a special number that occurs in exponential relationships its about 2.718 to 4 sf.
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    (Original post by lizard54142)
    e is the base of the natural logarithm.
    oh!
    Yes I do maths so I know all about e, i thought it was referring to the charge on an electron and just thought "what?!"

    with the graph, why is it everything to the right, i thought it was everything between R and D

    and for the proof, can someone quickly explain what happens between the two highlighted lines? I'm quite a confident mathematician but it's bugging me as I keep ending up with ln(-lambdaN0) and you can't take logs of a negative number...
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    (Original post by Mutleybm1996)

    with the graph, why is it everything to the right, i thought it was everything between R and D
    It's everything to the right as potential is from infinity to a point so its from D to infinity.
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    (Original post by will_iredale)
    It's everything to the right as potential is from infinity to a point so its from D to infinity.
    cheers

    what about the second part?
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    can someone briefly run through the highlighted lines? I didn't think you could take logs of a negative -lambdaN0???
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    (Original post by Mutleybm1996)
    cheers

    what about the second part?
    I'm not entirely sure about the negative but i believe it's because -lamdaN0 is a constant so i just replaced it with C, took logs then put it back in at the end.
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    (Original post by Mutleybm1996)
    can someone briefly run through the highlighted lines? I didn't think you could take logs of a negative -lambdaN0???
    You could consider it as ln| \lambda N_0 |, which is just an arbitrary constant, which they have called C
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    Say you have gamma and the time taken for observers on Earth
    How do you calculate the time taken for observers on a spacecraft?


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    Multiply it by gamma I think.

    Good luck for today everyone - I can usually hit an A* on these papers but OCR have a habit of screwing us over so who knows what will happen...
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    What was the equipotential q?


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    Did anyone else get 2.7x10^8?
    Also I think it went okay....few mistakes but not too bad!


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    (Original post by tpanesar)
    What was the equipotential q?


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    I got the one that looked like boobs
    Was considering going for the vertical line though


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    Was this one easier than last years?
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    (Original post by STATER)
    Was this one easier than last years?
    Yes


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    (Original post by Mutleybm1996)
    Yes


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    1-2 mark bump on boundaries you think?
 
 
 
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