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    (Original post by groceryboi)
    I put acceleration and deceleration increases. Got no idea what is correct. I went to that conclusion from the equation F=ma.
    The thing is, I don't think we told in the question that there was any friction between the car and the track.Usually when that happens we just assume there is none.
    Really though ,I think it may be something to do with momentum or what you put where the accelration and deceleration increaes.
    At this point though, I'm more interested in what the bloody answer was rather that if I lost a mark or not! xD
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    (Original post by FixUpMayte)
    still no unofficial mark scheme
    Do you think you can get one from your physics teacher, perhaps?
    I know one of my biology teachers made up an unofficial markscheme, although I haven't been able to have a look at it yet.
    But yeah, this year's physics exams have proven to be extremely divisive, and I know the exam happened days ago, but since I finished my exams now all I can do is worry.
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    what do you guys think the grade boundaries will be for an A, B, C, D and E for both of the papers together.
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    (Original post by Sapereaude54)
    That is eactly what I was thinking in the exam so I put the maximum velocity would have to increase.xD. I really don't know what the correct answer was now.
    Same bro.
    Only because if the mass decreases and if you use newtons second law of motion and imagine that both eh braking force and thrust force are constant , you will realise that if mass decreases then acceleration has to increase in order to maintain the same thrust and braking force.

    F = ma --> Imagine if F=5000N and m=500kg. then that means that a = 10ms^-2

    but now if the mass decreases , but the thrust force stays the same then that means that acceleration must increase.

    F = 5000N but m is now = 250kg then a = 20ms^-2

    hence the answer must be that the acceleration must be higher as well as the deceleration too. But i mean you are making assumptions like the braking force and thrust force is constant every lap which is impossible. Tbh AQA are terrible with the MC questions :/
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    (Original post by dragonblazer11)
    what do you guys think the grade boundaries will be for an A, B, C, D and E for both of the papers together.
    Well it depends on how the whole nation did. I mean AQA are gonna be generous apparently when they mark our papers. Also its the new spec so they might put a bit of a ease on the boundaries too.

    Im guessing that :

    A - 90
    B - 78
    C - 66
    D - 50
    E - 39

    I mean have you guys looked at The grade boundaries for Physics B last year?
    43/70 for an A and 33/70 for an A. AQA can go really low XD
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    (Original post by PawanAviator)
    Same bro.
    Only because if the mass decreases and if you use newtons second law of motion and imagine that both eh braking force and thrust force are constant , you will realise that if mass decreases then acceleration has to increase in order to maintain the same thrust and braking force.

    F = ma --> Imagine if F=5000N and m=500kg. then that means that a = 10ms^-2

    but now if the mass decreases , but the thrust force stays the same then that means that acceleration must increase.

    F = 5000N but m is now = 250kg then a = 20ms^-2

    hence the answer must be that the acceleration must be higher as well as the deceleration too. But i mean you are making assumptions like the braking force and thrust force is constant every lap which is impossible. Tbh AQA are terrible with the MC questions :/
    Well, the maximum velocity would still have to increase no matter what in order for momentum to be conserved also the driving force would have to change as mass has decreased anyway. In M5 mechanics we deal with systems of increasing and decreasing mass all the time and it's always solved using conservation of momentum.Although, I do agree with your reasoning. This question is so annoying, I just really want to know the answer-very poorly worded question!

    Also , what did you put for the seisometer question? Did you talk about how the pattern produced would correspond to the amplitude and frequency of the wave? I was completely confused by this question and no one in my class answered it from those I've spoken to!
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    Does anyone know the answer to the multiple choice question about the car crashing. I can remember that the option were 83N, 830N, 8300N. 830000N. I can remember myself putting 83,000N as the answer but that was a guess.

    Thanks.
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    (Original post by groceryboi)
    Does anyone know the answer to the multiple choice question about the car crashing. I can remember that the option were 83N, 830N, 8300N. 830000N. I can remember myself putting 83,000N as the answer but that was a guess.

    Thanks.
    Does anyone know the answer to the multiple choice question about the car crashing. I can remember that the option were 83N, 830N, 8300N. 83000N. I can remember myself putting 83,000N as the answer but that was a guess.

    Thanks
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    Are the second set of specimen papers available from the AQA website? If so, I can't find them. If not, please could you post a copy of paper 1 too? Thanks
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    (Original post by annacaroline)
    Are the second set of specimen papers available from the AQA website? If so, I can't find them. If not, please could you post a copy of paper 1 too? Thanks
    i have set 2 specimen if thats what u want??
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    (Original post by Sapereaude54)
    Well, the maximum velocity would still have to increase no matter what in order for momentum to be conserved also the driving force would have to change as mass has decreased anyway. In M5 mechanics we deal with systems of increasing and decreasing mass all the time and it's always solved using conservation of momentum.Although, I do agree with your reasoning. This question is so annoying, I just really want to know the answer-very poorly worded question!

    Also , what did you put for the seisometer question? Did you talk about how the pattern produced would correspond to the amplitude and frequency of the wave? I was completely confused by this question and no one in my class answered it from those I've spoken to!
    Yeah good point. same lol. You went up to M5?! thats really good.

    When i read that question , all that came to my mind was oscillations XD. yeah i kinda wrote the same thing , It thought of mechanical waves and transverse waves lol because the pen kinda acts like a particle. It vibrates "Quickly downwards" (S-waves) so it vibrates perpendicular to the direction of motion in some sort of way XD
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    (Original post by groceryboi)
    Does anyone know the answer to the multiple choice question about the car crashing. I can remember that the option were 83N, 830N, 8300N. 83000N. I can remember myself putting 83,000N as the answer but that was a guess.

    Thanks
    Yeah that was correct. if you managed to calculate it the exact answer was 83333.3N

    car had a mass of 500kg and moved at 10ms^-1
    "crumpled" a distance of 30cm? ===> 0.30m

    the Impulse on the car is 5000Ns as the velocity when it crashes is 0ms^-1
    Since I = F x t

    we need time so we use suvat
    s = 0.30
    u = 10
    v = ?
    a = ?
    t = t

    therefore if u use s = 0.5(u+v)t

    then you will get t = 0.06

    then I = F x t

    F = 5000/0.06
    F = 83333.3N

    and all for 1 F**king mark
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    Yep, please
    (Original post by Asad_2015)
    i have set 2 specimen if thats what u want??
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    (Original post by PawanAviator)
    Well it depends on how the whole nation did. I mean AQA are gonna be generous apparently when they mark our papers. Also its the new spec so they might put a bit of a ease on the boundaries too.

    Im guessing that :

    A - 90
    B - 78
    C - 66
    D - 50
    E - 39

    I mean have you guys looked at The grade boundaries for Physics B last year?
    43/70 for an A and 33/70 for an A. AQA can go really low XD
    Eh I would still prepare some lube just in case they aren't lenient.
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    (Original post by annacaroline)
    Yep, please
    there you go
    Attached Images
  1. File Type: pdf 7407-1 Paper 1 QP v1.0.pdf (424.8 KB, 557 views)
  2. File Type: pdf 7407-2 Paper 2 QP v1.1.pdf (619.8 KB, 648 views)
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    (Original post by PawanAviator)
    Yeah that was correct. if you managed to calculate it the exact answer was 83333.3N

    car had a mass of 500kg and moved at 10ms^-1
    "crumpled" a distance of 30cm? ===> 0.30m

    the Impulse on the car is 5000Ns as the velocity when it crashes is 0ms^-1
    Since I = F x t

    we need time so we use suvat
    s = 0.30
    u = 10
    v = ?
    a = ?
    t = t

    therefore if u use s = 0.5(u+v)t


    then you will get t = 0.06

    then I = F x t

    F = 5000/0.06
    F = 83333.3N


    and all for 1 F**king mark
    Thank you for explaining. Really appreciate it.
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    (Original post by PawanAviator)
    Yeah good point. same lol. You went up to M5?! thats really good.

    When i read that question , all that came to my mind was oscillations XD. yeah i kinda wrote the same thing , It thought of mechanical waves and transverse waves lol because the pen kinda acts like a particle. It vibrates "Quickly downwards" (S-waves) so it vibrates perpendicular to the direction of motion in some sort of way XD
    I think physicsmathstutor has uploaded model answers for the paper, but the papers are password protected,not sure if they're AQA either. I have emailed asking for it, so hopefully we can get the answer lol. I let you know if I hear anything.
    Best of luck and thanks for all your help!
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    Lol anyone good at hacking please hack them haha:ahee:
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    (Original post by Sapereaude54)
    I think physicsmathstutor has uploaded model answers for the paper, but the papers are password protected,not sure if they're AQA either. I have emailed asking for it, so hopefully we can get the answer lol. I let you know if I hear anything.
    Best of luck and thanks for all your help!
    thats fine man
    Good luck to you too!
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    (Original post by Asad_2015)
    there you go
    Thanks for this, do you have the mark scheme to it?
 
 
 
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