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    (Original post by KloppOClock)
    vectors questions are pretty much always the same i think. but id still rather have 7 questions so i can have more time to check answers
    Let's just hope it's easy. How have the C1 and C2 papers been?
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    (Original post by particlestudent)
    Let's just hope it's easy. How have the C1 and C2 papers been?
    c2 was pretty sound altho i messed up the discrimination question on c1 :/

    you?
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    is there a proof we need to learn for m1? I doubt it but I need to check
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    For this question, why is it not possible to just say x + 9 = 41 --> X = 41 - 9 = 32N? I thought resultant forces are the sum of the other forces :/?

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    (Original post by KloppOClock)
    c2 was pretty sound altho i messed up the discrimination question on c1 :/

    you?
    I'm in A2 so I've got C3 and 4 this year, along with M1. I just have to do well in M1 tomorrow to make life easier in C4 .

    I'm just working through Gold papers today, I don't know what else I can do...
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    (Original post by Don Pedro K.)
    For this question, why is it not possible to just say x + 9 = 41 --> X = 41 - 9 = 32N? I thought resultant forces are the sum of the other forces :/?

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    the forces are not acting in the same direction. You need to draw a force diagram (triangle in this case), showing the forces in series (one after the other). The resultant is the diagonal joining the start point to the end point
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    Good luck for tomorrow guys I'm ******** it as always!!
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    (Original post by candol)
    the forces are not acting in the same direction. You need to draw a force diagram (triangle in this case), showing the forces in series (one after the other). The resultant is the diagonal joining the start point to the end point
    Ah alright, thanks

    Also, is it just me being stupid (again) or is the equation for solving (-->) in this solution wrong? Surely it should be
    F + Rcos(60) = 30cos(30)?

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    (Original post by Don Pedro K.)
    Ah alright, thanks

    Also, is it just me being stupid (again) or is the equation for solving (--> in this solution wrong? Surely it should be
    F + Rcos(60) = 30cos(30)?

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    that's the same thing
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    (Original post by candol)
    that's the same thing
    But in their equation, F - 30cos(30) = Rcos(60) so F = Rcos(60) + 30cos(30)

    but if it was F + Rcos(60) = 30cos(30) to begin with, F would = 30cos(30) - Rcos(60), which isn't the same as above?
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    (Original post by Don Pedro K.)
    But in their equation, F - 30cos(30) = Rcos(60) so F = Rcos(60) + 30cos(30)

    but if it was F + Rcos(60) = 30cos(30) to begin with, F would = 30cos(30) - Rcos(60), which isn't the same as above?
    quite right its not - do apologise. wasn't paying full attention. There equation looks right, but why would you draw 2 diagrams for a question?
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    (Original post by candol)
    quite right its not - do apologise. wasn't paying full attention. There equation looks right, but why would you draw 2 diagrams for a question?
    Hmm I'm not sure :/ I have a feeling that it's wrong but I don't know to be honest! Zacken could you have a look?
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    (Original post by Don Pedro K.)
    Hmm I'm not sure :/ I have a feeling that it's wrong but I don't know to be honest! Zacken could you have a look?
    Have you got the original question - the diagram is fine, (it is BASIC forces) but you really should have everything on the one diagram. It is not obvious to me what the original question was (cant be statics, it would be moving down??)
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    (Original post by Don Pedro K.)
    Hmm I'm not sure :/ I have a feeling that it's wrong but I don't know to be honest! Zacken could you have a look?
    It's correct.

    If you resolve to the right, you get F - 30 cos 30.

    This is the resultant force to the right. The resultant force to the right is also given by R cos 60

    So F - 30 \cos 30= R \cos 60.

    They've been drawn on different diagrams for a reason, you're treating them as though they are the same diagram.
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    Name:  Screen Shot 2016-06-07 at 13.15.24.png
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Size:  208.7 KB sorry for the crap quality but does anyone know how to do this question? I can't find a mark scheme for it anywhere
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    (Original post by Zacken)
    It's correct.

    If you resolve to the right, you get F - 30 cos 30.

    This is the resultant force to the right. The resultant force to the right is also given by R cos 60

    So F - 30 \cos 30= R \cos 60.

    They've been drawn on different diagrams for a reason, you're treating them as though they are the same diagram.
    I see, I see. Why do we use two separate diagrams then?
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    (Original post by Strom)
    Good luck for tomorrow guys I'm ******** it as always!!
    Ayy, optimism ftw

    (Original post by candol)
    the forces are not acting in the same direction. You need to draw a force diagram (triangle in this case), showing the forces in series (one after the other). The resultant is the diagonal joining the start point to the end point
    Post 666 and you mention triangle :teehee:
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    (Original post by bertolli1)
    Name:  Screen Shot 2016-06-07 at 13.15.24.png
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Size:  208.7 KB sorry for the crap quality but does anyone know how to do this question? I can't find a mark scheme for it anywhere
    part a) suvat
    s=h
    A=-9.8
    t=5
    u=20

    partb)
    Find V using suvat for the first ball
    You can now work out 3/4 v for the second ball
    Do suvat with v=3/4V, u=w, a=9.8, s= height found from part a
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    (Original post by bertolli1)
    Name:  Screen Shot 2016-06-07 at 13.15.24.png
Views: 141
Size:  208.7 KB sorry for the crap quality but does anyone know how to do this question? I can't find a mark scheme for it anywhere
    For (a)

    s = -h, u = 20, v = v, a = -9.8, t = 5

    Shove into suvat and solve for h.

    (Original post by Don Pedro K.)
    I see, I see. Why do we use two separate diagrams then?
    I wouldn't use two diagrams. I'd just say resultant to the right is F - 30 cos 30 and to the bottom is 30 sin 30 or w/e and work from there without using R.
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    (Original post by candol)
    part a) suvat
    s=h
    A=-9.8
    t=5
    u=20
    Check your s.
 
 
 
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