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    Hi, can anyone help me with part (ii) of this question.. this is what I've got and after that I'm stumped! Thanks!
    P cos 60º = Fr + 30 g sin 60º


    R = P sin 60º + 30 g cos 60º
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    (Original post by clarewithnoi)
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    Hi, can anyone help me with part (ii) of this question.. this is what I've got and after that I'm stumped! Thanks!
    P cos 60º = Fr + 30 g sin 60º


    R = P sin 60º + 30 g cos 60º
    Fr = mu R
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    (Original post by TenOfThem)
    Fr = mu R
    I tried that but I ended up wit 1900N when the answer was 1440N Do you have to rearrange the equations or something? I'm so confused!
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    (Original post by clarewithnoi)
    I tried that but I ended up wit 1900N when the answer was 1440N Do you have to rearrange the equations or something? I'm so confused!
    yep

    Used your equations

    1440
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    (Original post by TenOfThem)
    yep

    Used your equations

    1440
    I'm still getting the wrong answer! I just checked the markscheme, the only part I didn't get was 15g root 3 and 15g in my equations, can you explain where they came from?
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    (Original post by clarewithnoi)
    I'm still getting the wrong answer! I just checked the markscheme, the only part I didn't get was 15g root 3 and 15g in my equations, can you explain where they came from?
    The fact that cos(30) = root3 / 2
 
 
 
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