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    it was challenging.......... and the thing that pissed me off was where it asked to state the quark composition for a proton and a neutron

    at first i put the right answer, then i crossed the ****ing thing out and changed it which SUCKED, it then asked us to use the quark compositions to show some thing after and i put under the proton the correct quark composition, showing the correct quark comp. of a proton and a neutron so maybe the examiner could give me benefit of the doubt? I ****ING HOPE SO. PLEASE LORDDDDD
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    (Original post by DazYaYYY)
    it was challenging.......... and the thing that pissed me off was where it asked to state the quark composition for a proton and a neutron

    at first i put the right answer, then i crossed the ****ing thing out and changed it which SUCKED, it then asked us to use the quark compositions to show some thing after and i put under the proton the correct quark composition, showing the correct quark comp. of a proton and a neutron so maybe the examiner could give me benefit of the doubt? I ****ING HOPE SO. PLEASE LORDDDDD
    Proton: uud
    Neutron: udd

    It's obvious, as the u quark has a +2/3 charge and the u quark has a -1/3 charge, hence it's easy to deduce - Providing that you know that no other quark apart from these 2 is involved in the composition of the proton and the neutron.
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    that was only worth a few marks

    i'm putting in my two cents now, cos i really dont want to know what the answers were - but my feelings towards that module were quite good. I think i got most of the marks - things i wasnt sure on tended to only be 1 or 2 mark questions, so i wont lose much there. Generally i think i've done enough to get my A overall, so i'm happy!
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    (Original post by Checkey)
    Proton: uud
    Neutron: udd

    It's obvious, as the u quark has a +2/3 charge and the u quark has a -1/3 charge, hence it's easy to deduce - Providing that you know that no other quark apart from these 2 is involved in the composition of the proton and the neutron.
    yes i showed that the proton and neutron had quarks of uud and udd respectively, AFTER the question, but the question before i crossed it out and changed my thoughts therefore i contradicted myself, i shuda left it how it was but maybe the examiner can give benefit of the doubt? blahhhhh
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    Twas an easy paper. THe equations I had forgotten (Resistivity, Specific Heat Capacity) I used the unit given to derive where and what values I was looking for.

    The quark composition equation... how did it mean 'Simplify?' I dont think I did very well on that, but in total it was only 4 marks, plus it was easy to work out the composition of the Pion+ particle.

    Overall, it was a doddle, thank god, because Unifying concepts I screwed up

    Anyone have any questions and Ill try to remember what I put!! (12.1 hours for the cyclist... etc)
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    oh gosh.....
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    (Original post by Urdegish)
    Twas an easy paper. THe equations I had forgotten (Resistivity, Specific Heat Capacity) I used the unit given to derive where and what values I was looking for.

    The quark composition equation... how did it mean 'Simplify?' I dont think I did very well on that, but in total it was only 4 marks, plus it was easy to work out the composition of the Pion+ particle.

    Overall, it was a doddle, thank god, because Unifying concepts I screwed up

    Anyone have any questions and Ill try to remember what I put!! (12.1 hours for the cyclist... etc)
    Sounds easy, considering we do particle physics and specific heat capacity etc. at AS Level on the AQA syllabus.
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    (Original post by Urdegish)
    work out the composition of the Pion+ particle
    The Pion+ particle is a meson, hence its quark composition must be a quark and an anti-quark.

    It has a +1 charge and has a strangeness of 0 (It probably said this on the exam paper I presume).

    Quark Composition: u, d-bar.
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    (Original post by Urdegish)
    Twas an easy paper. THe equations I had forgotten (Resistivity, Specific Heat Capacity) I used the unit given to derive where and what values I was looking for.

    The quark composition equation... how did it mean 'Simplify?' I dont think I did very well on that, but in total it was only 4 marks, plus it was easy to work out the composition of the Pion+ particle.

    Overall, it was a doddle, thank god, because Unifying concepts I screwed up

    Anyone have any questions and Ill try to remember what I put!! (12.1 hours for the cyclist... etc)
    the specific heat capacity and the resistivity was ok p = RA / l therefore l = RA / p
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    is activity measured in Bq ? hoping so..
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    (Original post by Checkey)
    The Pion+ particle is a meson, hence its quark composition must be a quark and an anti-quark.

    It has a +1 charge and has a strangeness of 0 (It probably said this on the exam paper I presume).

    Quark Composition: u, d-bar.
    lucky me, I made an educated guess on that one, seems I was right, if you are... well that's one mark I haven't lost .

    Overall not bad. I don't really like the questions about the JET project because the textbook doesn't seem to say much about it. I just wrote down most of the stuff I could think of to do with nuclear fusion. Maybe 6/11 of that question, dunno.
    And I got 12 hours of pedalling on the synoptic, with a length of about 7 km. anyone else get that? heh. edit: oh yeh missed the answer to my q above.

    Did remember E = mc delta theta tho...

    And I couldn't quite remember how to derive that r = mv/Bq formula, unfortunately.

    Rest of it I was fairly happy with.
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    (Original post by DazYaYYY)
    is activity measured in Bq ? hoping so..
    yes, activity is in counts per second, or Bequerel
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    (Original post by elpaw)
    activity is in counts per second
    Yep, Count Rate.

    Although we aren't supposed to learn this until A2, despite being taught it in Year 11. :rolleyes:
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    (Original post by elpaw)
    yes, activity is in counts per second, or Bequerel
    ok ty

    when that nuclei went thru beta decay, did your atomic number increase by one each time, and that a positron was emitted?
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    Its all looking good then And yeah, I knew the composition easy, but instead of all the meson mumbo jumbo I just summed up the U's and D's on both sides, and found what was needed to balance them

    That damn carbon cycle question sucked... did you just have to draw a long line of equations, with the electrons being given off, and some of the lines have Hydrogen above them (to show that this reaction occurs in the presence of hydrogen)?
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    (Original post by DazYaYYY)
    ok ty

    when that nuclei went thru beta decay, did your atomic number increase by one each time, and that a positron was emitted?
    Beta decay has two emisions, electrons and positrons.

    The atomic number goes UP if an electron is given off

    The atomic number goes DOWN if a positron is given off
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    (Original post by Urdegish)
    Beta decay has two emisions, electrons and positrons.

    The atomic number goes UP if an electron is given off

    The atomic number goes DOWN if a positron is given off
    1/2
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    (Original post by DazYaYYY)
    ok ty

    when that nuclei went thru beta decay, did your atomic number increase by one each time, and that a positron was emitted?
    A positron is emitted in Beta + Decay, an electron is emitted in Beta minus decay.

    If the nuclei underwent Beta + decay, each time a positron is emitted a proton changes into a neutron by an up quark changing into a down quark.

    The opposite occurs if Beta minus decay occurs - Electron is emitted at high speed and a neutron changes into a proton over time.
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    (Original post by Urdegish)
    Its all looking good then And yeah, I knew the composition easy, but instead of all the meson mumbo jumbo I just summed up the U's and D's on both sides, and found what was needed to balance them

    That damn carbon cycle question sucked... did you just have to draw a long line of equations, with the electrons being given off, and some of the lines have Hydrogen above them (to show that this reaction occurs in the presence of hydrogen)?

    hmm I just learned that formula out of the textbook..

    4*H-1 -> He-4 + 2e + 2v

    Same as the Hydrogen cycle... If I remember the question right, anyway.
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    Pants!
 
 
 
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