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    Just wanted to know what part c of this question means? It's worded in a very bizarre way! Many thanks
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    part c asks for the time between the moment when sphere is first at p and when it passes p again after the string breaks. (does it make sense now??)
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    Is it just asking you to find the time between the sphere beginning to move upwards, and the time it returns to P? I see they've given you a quadratic with T defined after the string breaks, which means at T = 0, the sphere is 1.8m above P - this is probably an important clue?
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    (Original post by Brudor2000)
    part c asks for the time between the moment when sphere is first at p and when it passes p again after the string breaks. (does it make sense now??)
    Thank you so much! Now how do you go about doing this question?
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    (Original post by plklupu)
    Is it just asking you to find the time between the sphere beginning to move upwards, and the time it returns to P? I see they've given you a quadratic with T defined after the string breaks, which means at T = 0, the sphere is 1.8m above P - this is probably an important clue?

    Thank you so much! Now how do you go about doing this question?
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    to find time after string breaks use the quadratic equation given in b. then u need to find time when sphere is at p for first time to when the string breaks ( i am trying to figure that out). then just add both the times together to get total time.
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    (Original post by Brudor2000)
    to find time after string breaks use the quadratic equation given in b. then u need to find time when sphere is at p for first time to when the string breaks ( i am trying to figure that out). then just add both the times together to get total time.
    Thank you! I'll give that a go now too!
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    (Original post by h26)
    Thank you so much! Now how do you go about doing this question?
    My gut instinct is that it's just the value of T + however long it took to travel 1.8m up in the first place, but that seems way too simple for 4 marks. I think you need to use the acceleration from part iv) for that initial 1.8m bit.
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    Damn, @Brudor2000 is beating me to it, haha!
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    (Original post by plklupu)
    Damn, @Brudor2000 is beating me to it, haha!
    @plklupu lol
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    I got 1.99s in total - have you got a mark scheme where you can check?
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    (Original post by plklupu)
    I got 1.99s in total - have you got a mark scheme where you can check?
    It's 2.19 seconds - actually it's not

    Edit: actually ill double check the time
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    (Original post by plklupu)
    I got 1.99s in total - have you got a mark scheme where you can check?
    Here is the link to the paper to save time:
    http://mei.org.uk/files/papers/m109ju_livn.pdf
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    (Original post by h26)
    It's 2.19 seconds but ill post the mark scheme as well

    Edit: actually ill double check the time
    Oops, I ****ed up me acceleration for the initial 1.8m - I wrote down 3ms^-2, but it's 2.5. You're right about 2.19s.
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    (Original post by plklupu)
    I got 1.99s in total - have you got a mark scheme where you can check?
    http://mei.org.uk/files/papers/m109ju_livn.pdf
    here is the link to mark scheme. have a look at it
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    (Original post by plklupu)
    Oops, I ****ed up me acceleration for the initial 1.8m - I wrote down 3ms^-2, but it's 2.5. You're right about 2.19s.
    No wait I thought I made a mistake
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    (Original post by h26)
    No wait I thought I made a mistake
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    Huh, I've no clue where they got that alternative a.

    https://imgur.com/JmvXiN0
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    (Original post by plklupu)
    Huh, I've no clue where they got that alternative a.

    https://imgur.com/JmvXiN0
    Lol me too! I worked it out in the end. But I solved 4.9T^2 -3T -1.8=0 to t=0.985 and then did v=u+at like you did to get 1.2 seconds. Added them together to get 2.19 seconds
    Thanks for the pic of your working out
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    (Original post by h26)
    No wait I thought I made a mistake
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    Page 54 is where C is.
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    (Original post by h26)
    Lol me too! I worked it out in the end. But I solved 4.9T^2 -3T -1.8=0 to t=0.985 and then did v=u+at like you did to get 1.2 seconds. Added them together to get 2.19 seconds
    Thanks for the pic of your working out
    No probs! Happy to help
 
 
 
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