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    (Original post by Euclidean)
    I'd say that because of the way they presented the diagram, V is infact the magnitude of the velocity of whatever that particle was (memory is failing me) and that this, coupled with the direction makes up the velocity of -V.

    Hence \Delta \vec{p} = mv - MV = 0

    But I also strongly think AQA will have to accept either \pm answer simply because they didn't make their intention clear enough.

    Sorry I didn't sit the EMPA, may be worth checking past grade boundaries, looking for the grade/UMS mark you want and calculating a mean raw mark for that UMS mark.
    I see what you mean. The only reason why I disagree is because normally in momentum questions with arrows present, they specifically state that an object is travelling at a certain speed - they never mention velocity, so you infer from the diagram and couple the speed with the direction of the arrow to form the velocity. In this question, they used the word velocity for the first time (AFAIK), so I thought to ignore the arrows as I didn't think it would be needed, since what's given is a vector quantity already. But I also strongly think that they should accept both.

    And no worries.
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    (Original post by tanyapotter)
    By the way, have you done the EMPA? Would you happen to have any grade boundary predictions for it?
    I did the EMPA.

    Thought that Task 2 (interrupted pendulum) and the written part were OK, although question 2 in the written paper (the mass-spring system) was a bit weird.

    Task 1 (electric field, capacitor discharge) I thought was one of the hardest they have set. So about average boundaries overall?
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    (Original post by marioman)
    I did the EMPA.

    Thought that Task 2 (interrupted pendulum) and the written part were OK, although question 2 in the written paper (the mass-spring system) was a bit weird.

    Task 1 (electric field, capacitor discharge) I thought was one of the hardest they have set. So about average boundaries overall?
    Thanks! Do you think 36/55 would be enough for, say, a B then?
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    (Original post by tanyapotter)
    Thanks! Do you think 36/55 would be enough for, say, a B then?
    Easily. That will be around an A given recent boundaries.
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    (Original post by marioman)
    Easily. That will be around an A given recent boundaries.
    That's reassuring. I need to scrape a B this year if I want an A overall, and the more I look at the unofficial mark scheme, the more unsure I get that I've done enough. It's driving me insane!!
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    Agh samee, every time I look at it feel like ive done worse. Do you have any ideas to what the grade boundaries will be for part A?
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    (Original post by boyyo)
    Agh samee, every time I look at it feel like ive done worse. Do you have any ideas to what the grade boundaries will be for part A?
    The MC grade boundaries will probably drop by 1.
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    (Original post by kingaaran)
    The MC grade boundaries will probably drop by 1.
    Do you think the grade boundaries for the Unit 4 paper as a whole will be similar to June 2014's (the highest so far) or will it be even higher, in your opinion?
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    June 2014 had standard boundaries for A, B, C, etc., it was only the A* boundary that got bumped up. The reason for that was mainly because that year's Unit 5 had extremely low boundaries (46/75 for an A and 52/75 for an A*) and keeping the A* at the usual point for Unit 4 would have resulted in way more people getting an A* than usual. Doubt that will happen again this year because Unit 5 was fine.
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    (Original post by marioman)
    June 2014 had standard boundaries for A, B, C, etc., it was only the A* boundary that got bumped up. The reason for that was mainly because that year's Unit 5 had extremely low boundaries (46/75 for an A and 52/75 for an A*) and keeping the A* at the usual point for Unit 4 would have resulted in way more people getting an A* than usual. Doubt that will happen again this year because Unit 5 was fine.
    Would you say it's sensible to assume that unit 5 boundaries will be similar to June 2015, and unit 4 boundaries will be similar to June 2014?
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    (Original post by tanyapotter)
    Would you say it's sensible to assume that unit 5 boundaries will be similar to June 2015, and unit 4 boundaries will be similar to June 2014?
    Yes, but I think the A* boundary will be lower for this Unit 4 than in June 2014.
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    (Original post by tanyapotter)
    Do you think the grade boundaries for the Unit 4 paper as a whole will be similar to June 2014's (the highest so far) or will it be even higher, in your opinion?
    No it won't be similar to June 2014. It wasn't that easy. I think it'll be around 60 for an A*.*
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    (Original post by kingaaran)
    No it won't be similar to June 2014. It wasn't that easy. I think it'll be around 60 for an A*.*
    Do you think it'll be the same for the A?
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    (Original post by boyyo)
    Do you think it'll be the same for the A?
    No, it'll be whatever usually is the case when the A* boundary is 60, I reckon
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    Anyone have any idea what the ISA boundaries will be like?

    Does this sound about right for PHYA4?

    120 UMS = 65/75
    108 UMS = 60/75
    A = 55/75
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    (Original post by Cadherin)
    Anyone have any idea what the ISA boundaries will be like?

    Does this sound about right for PHYA4?

    120 UMS = 65/75
    108 UMS = 60/75
    A = 55/75
    That gap between grades will be about 2 marks bigger, I think. More like:*

    Full - 67/75
    A* - 60/75
    A - 53/75
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    (Original post by kingaaran)
    That gap between grades will be about 2 marks bigger, I think. More like:*

    Full - 67/75
    A* - 60/75
    A - 53/75
    Oh really? Might be tight for full for me then, I lost 3 on the McQ. Gives me 5 to drop on the paper itself :eek:
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    (Original post by Euclidean)
    Oh really? Might be tight for full for me then, I lost 3 on the McQ. Gives me 5 to drop on the paper itself :eek:
    Haha - that's the trouble with papers we find easier than usual :s


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    (Original post by kingaaran)
    Haha - that's the trouble with papers we find easier than usual :s


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    Praying I don't miss the * in Physics, I'll be a bit upset
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    (Original post by Euclidean)
    Praying I don't miss the * in Physics, I'll be a bit upset
    Hopefully you don't! I wasn't very confident after Unit 4, just because I didn't find it as easy as everyone else claimed. But after Unit 5, I feel slightly more confident*
 
 
 
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