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    (Original post by Wings)
    approx. 2.5m it has to be half the wavelength of original wave since it starts 180 degrees outa phase
    I got 2.3.

    Worked out Lambda by using v = fLambda

    Then divided it by 2, is that what you did?
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    yeh thats correct
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    For the question where it had the electron as a standing wave, when it told you to calculate the Potential energy, did you use the formula? I thought you needed to use the formula but they didnt give you the charges of an electron/proton so I just went back and found the charge of an electron...

    Also, for the graph question, did you find the numbers of squares x value of one square, times the mass of the satellite?
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    Btw wen u said it will not exceed 1.5% you were rite.. so relax.

    To work out intensity u had to say

    Intensity= Activity in one sec X energy per molecule

    The activity is found by saying A=N lambda (u know lambda since u had to work it out)
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    (Original post by Wings)
    Btw wen u said it will not exceed 1.5% you were rite.. so relax.

    To work out intensity u had to say

    Intensity= Activity in one sec X energy per molecule

    The activity is found by saying A=N lambda (u know lambda since u had to work it out)
    Did you get 1.5% as well?
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    Yeh i got 1.5%

    The charge question is the only one i cudnt do. didnt give me charge ??

    And yes u just had to times area by mass of satellite. However, i missed the estimate bit and worked it out with the formulae. The mass of sun cud easily be worked out by taking a point on the graph and saying g= Gm/r^2 where m is mass of earth.

    Eith way is correct.. I just did it the much longer way..o well
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    (Original post by Wings)
    Yeh i got 1.5%

    The charge question is the only one i cudnt do. didnt give me charge ??

    And yes u just had to times area by mass of satellite. However, i missed the estimate bit and worked it out with the formulae. The mass of sun cud easily be worked out by taking a point on the graph and saying g= Gm/r^2 where m is mass of earth.

    Eith way is correct.. I just did it the much longer way..o well
    What charge question are we talking about here?
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    work out potential energy of electron.. some reason that got me???

    Pe= Qq/ (4 pi E r)

    Where the heck was Q or q (ie charges of particles.. or were i to simply assume they were +1 and -1 ???)
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    (Original post by Wings)
    work out potential energy of electron.. some reason that got me???

    Pe= Qq/ (4 pi E r)

    Where the heck was Q or q (ie charges of particles.. or were i to simply assume they were +1 and -1 ???)
    Yeh thats the question Im on about

    I went back, found the charge of an electron(1.6x10^-19) and seen as the chrage on a proton is equal but opposite, its just (1.6x10^-19)^2

    Thats how I did it, but like you say, they didnt give us charges so maybe they were expecting a different method?
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    Well its not TOO many marks anyway so shudnt matter too much.. especially if around 58/100 wud be an A.

    So relax.. at least all the physics is OVER!!!

    lol

    What uni u hoping to goto m8?
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    (Original post by Wings)
    Well its not TOO many marks anyway so shudnt matter too much.. especially if around 58/100 wud be an A.

    So relax.. at least all the physics is OVER!!!

    lol

    What uni u hoping to goto m8?
    York, you?
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    Hopefully UCL : )

    What u studying?
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    (Original post by Wings)
    Hopefully UCL : )

    What u studying?
    Physics :rolleyes:
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    Also, I thought it was quite strange having 2 questions saying stuff like:

    'Show that the kinetic energy of the electron can be represented by this equation 3 marks for rearranging equations..I have to add I though they were pretty tricky equations as well :|
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    ive did so terrible, need an A but its looking very unlikely! Did ne 1 get 1m fot the length for da plate, plz say yes cuz its bout da only one i cud do
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    (Original post by Marie123)
    ive did so terrible, need an A but its looking very unlikely! Did ne 1 get 1m fot the length for da plate, plz say yes cuz its bout da only one i cud do
    Yes I got 1m, I thought I did it wrong though.

    I did Ft = mv

    found t, multiplied by 0.80
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    Are you talking bout how the long the plate has to be in order to catch the dust particle??
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    (Original post by imasillynarb)
    York, you?
    what's your offer and what are you expecting?
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    (Original post by Wings)
    Are you talking bout how the long the plate has to be in order to catch the dust particle??
    Yeh
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    (Original post by elpaw)
    what's your offer and what are you expecting?
    BBB, god knows what Im gonna get though. I was hoping for AAB, but it seems increasingly unlikely, and depending on how chemistry goes tomorrow Itll probably be BBC Why?
 
 
 
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