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    Hello, I just did the brutal question paper below and I got only 47/80. I have corrected some of my errors, but not all. I do not understand how some of the mark scheme answers are formed and I do not actually understand them.

    QP:
    https://docs.google.com/viewer?a=v&q...8gJZz4tLbBaBzw
    MS:
    https://docs.google.com/viewer?a=v&q...UwEbE4PzfT1wOA

    The questions which I feel completely clueless:confused: on are 16aii, 4, 5 and 14. The questions are too hard for me and I need some explanations.

    THANKS A LOT!!!!!!!!!!
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    I figured out question 5. The vertical component of R is the same but opposite to W so that W is cancelled out. But The horizontal component of R maes it accelerate down the surface. But I still need help on questions 6aii, 4 and 14 please, please, please.

    Thanks a lot
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    well for q4 since R is perpendicular to the slope ( or inclined surface ) the component in that direction has to be zero... if you are not sure then work out Rcosθ when θ is 900
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    I understand question 4

    Here's my working out:
    cos90=Component/W
    cos90 X W=component

    cos 90=0

    hence component=0
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    If you just tilt your head a bit, or the paper, it still makes sense!
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    4 and 5 make sense now

    Just 14 and 16aii are killing me
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    For question 14 when the deceleration occurs, surely a resultant force acts to the left hand side to decelerate the train. Look at the direction of travel. So wouldn't A be pushed into their seat and both B and C be pushed to the left??? The MS says the opposite pretty much and I really want to understand how to tackle this killer question.

    Thanks
 
 
 
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