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AQA MM1B - Mechanics 1 -Tuesday 21st June 2016 watch

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    (Original post by dm999)
    you need to think about the components of the velocities.

    I component/divided by J component leads directly to direction

    so this is the same when the velocities are parallel

    Still very hard for M1 and the AS students
    Maybe that's what AQA are pushing towards, harder exams.
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    (Original post by jtebbbs)
    SAME horizontal plane only means that they are at the same height, i.e. don't move up or down relative to the ground. The question specifically said "instant" at which the velocities are parallel, which straight away means there's only one value for t - which is 12. The big misconception is really that most people didn't realise that when two velocities are parallel, one is a multiple of the other but they are not necessarily the same magnitude. With your method, if you put t=5 into the expressions for both components of both velocities, you would find that the velocities are neither the same, nor multiples of each other, so could not possibly be parallel.

    The key knowledge that AQA were looking for here was that multiples of vectors are parallel, which is GCSE knowledge, not Core 4 (although it is used briefly again in Core 4 with vectors in i, j and k) and that is what made this a 10 mark question when everything else it was asking had come up in 6-8 markers in previous years.

    I'm not saying it wasn't a tough question, it was, but that is what they were testing for.
    On which exam board for GCSE is this on because I certainly didn't learn it 😂
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    I would think its intentional, it seems the exams are getting harder each year,

    The thing that stands out about making this question difficult, is that it does not lead you into the solution at all.

    It could say, find the velocity of each particle at time t.

    And the position at time t.

    Then the distance between the particles when the velocities are parallel.

    More candidates would then score at least some of the marks.

    Some candidates might even score full marks, that didnt have a clue where to start.

    Its certainly aimed at "sorting" out the grade As
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    (Original post by rainbowtwist)
    On which exam board for GCSE is this on because I certainly didn't learn it 😂
    Its how you interpret it,

    All exams boards do tangents at gcse.

    The direction is purely that, the i component divided bu the j component.
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    yeah i did
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    How did you guys get 1.76 for question 7a. I keep trying and i got 1.9 something... :/
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    (Original post by the_malis)
    How did you guys get 1.76 for question 7a. I keep trying and i got 1.9 something... :/
    you have to make s=1 and a= -9.8 I think?
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    (Original post by kiiten)
    you have to make s=1 and a= -9.8 I think?
    I'm an idiot, i made s=-1 for some reason. How many marks would I lose for thatc question, do you think?
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    (Original post by the_malis)
    I'm an idiot, i made s=-1 for some reason. How many marks would I lose for thatc question, do you think?
    I think that would still work if you put a= 9.8 (not sure though). It depends really (how many marks was that ques i forgot xD).

    Youll probably get some method marks and possibly error carried forward for later ques. Maybe half marks in total?
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    For the 10 marker I did everything right until working out the position of B where I did not add it's original position vector so I got a distance much smaller then 106 - how many lost?
    With the 7 marker I also did everything right until right at the end where I forgot to square the cos50 so I only divided by cos50 not cos^2(50) and so got 10.6 instead of 13.2 - how many lost again?
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    (Original post by Colsop50)
    ok thanks, I'm a further maths student and managed to do 6x4 = 32 instead of 24 :-(
    haha I did 3+7=11 in one of them, so I know how you feel!
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    (Original post by SM-)
    For the 10 marker I did everything right until working out the position of B where I did not add it's original position vector so I got a distance much smaller then 106 - how many lost?
    With the 7 marker I also did everything right until right at the end where I forgot to square the cos50 so I only divided by cos50 not cos^2(50) and so got 10.6 instead of 13.2 - how many lost again?
    Maybe 3 marks? For the 7 marker possibly 2 marks you might want someone else to double check as im not too sure.
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    (Original post by Sam Webb)
    You can't do 16/1.7 because 1.7 was the time taken for the ball to hit the front edge, you had to rework out the time taken to be 1.9 as it would take longer to go further then do 16/1.9 etc
    I said the intiaI veIcoity was xsin(theta) and worked at an expression for t with x as verticaI distance is the same. I added 3 to previous horizontaI distance and then times my verticaI time by 2 and subbed that t into a suvat. got around 13.
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    (Original post by That bloke 2016)
    I'm a bit late but I'm pretty sure it was 081 degrees as it seemed too big so I flipped the opp/adj fraction to ensure it was the most sensible answer and about 7.something degrees came out, confirming it was actually about 081

    note: there will still be a fair few method marks for getting that far.
    Wait sorry, I'm confused so what was the actual correct answer?
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    any grade boundary predictions?
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    Grade boundaries are out!

    A 51/75
    b 45/75
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    Jeez... so 58ish for 90% UMS? Good luck everyone!
    • Welcome Squad
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    Welcome Squad
    (Original post by Chickenslayer69)
    My opinion on boundaries:

    Full UMS: 66
    A: 51
    B: 44
    C: 38
    D: 32
    E: 26

    Please don't take this as absolute, it is my prediction, but I am usually accurate when predicting boundaries. Expect something around this.
    your predictions right
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    helloo, has anyone got the june 2016 paper for M1B? I've already done the mock and will get it after next week but thought I'd try to redo some of the questions I struggled with!
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    2016 q7 helpppppp!!!!
 
 
 
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