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    http://filestore.aqa.org.uk/subjects...W-QP-JUN10.PDF
    http://filestore.aqa.org.uk/subjects...W-MS-JUN10.PDF

    Q6ciii) I cant do it for some reason

    My values
    S=4
    U=3.92 They make this negative im not sure why?
    V=9.68
    A=9.8
    T=?

    Surely if they make u negative then they'd make v negative because those values correspond to Particle A not B
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    (Original post by Sniperdon227)
    http://filestore.aqa.org.uk/subjects...W-QP-JUN10.PDF
    http://filestore.aqa.org.uk/subjects...W-MS-JUN10.PDF

    Q6ciii) I cant do it for some reason

    My values
    S=4
    U=3.92 They make this negative im not sure why?
    V=9.68
    A=9.8
    T=?

    Surely if they make u negative then they'd make v negative because those values correspond to Particle A not B
    Before the string breaks, B is moving up towards the pulley (since A is the heavier particle).

    Once the string breaks, B will continue to move up but it's acceleration will only be due to gravity which acts downwards.

    So if you take downwards as positive then u will be negative when the string breaks. Eventually the particle will change direction and move down towards the surface. But the initial velocity is upwards.
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    For A
    S=4
    U=3.92
    V=9.68
    A=9.8
    T=?

    For B
    S=4
    U=-3.92
    V=9.68
    A=9.8
    T=?

    Can you please explain it more, I still dont understand
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    (Original post by Sniperdon227)
    For A
    S=4
    U=3.92
    V=9.68
    A=9.8
    T=?

    For B
    S=4
    U=-3.92
    V=9.68
    A=9.8
    T=?

    Can you please explain it more, I still dont understand
    Before the string break, particle A is moving downwards and particle B is moving upwards. Since the direction of A and B are different, so the sign is different. If the mark scheme has set a positive direction as downwards, then B will be moving in a negative direction. Therefore the signs of the particle A and B are different
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    (Original post by Sniperdon227)
    Can you please explain it more, I still dont understand
    If you could tell us why you think u should be positive then that will help us explain why it shouldn't be.
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    OMG Ive been reading the question wrong all this time it goes up 4m then goes down 8m so
    S= -4
    U=3.92
    V=9.68
    A=9.8
    T=?


    this is taking up to be positive
    t=1.39
 
 
 
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