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    Massive apologies for the state of my work lol. Don't bother reading it if you don't want to!
    ive got part 1 of the Q regarding the distance (7m)
    but for the time surely it's the time taken to travel through the air (I got 20/7seconds) plus 2x the time taken from top of water to bottom of water

    but the answers wrong and I'm not sure what went wrong.. Thanks in advance

    (Ans=3.86s)
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    Time in air is correct.

    water - s = 0, u = 28. a = -56
    so, 0 = 28t + -0.5x-56xt^2 (s=ut+0.5at^2 rule)

    0 = 28t - 28t^2

    Factorise: 0 = 28t(1-t)

    So either 28t = 0...so t = 0 - nope

    OR 1 - t = 0...so t = 1. - yes.

    time in air + time in water = 3.86s. as 2.86 + 1 =3.86
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    (Original post by Jackasnacks)
    Massive apologies for the state of my work lol. Don't bother reading it if you don't want to!
    ive got part 1 of the Q regarding the distance (7m)
    but for the time surely it's the time taken to travel through the air (I got 20/7seconds) plus 2x the time taken from top of water to bottom of water

    but the answers wrong and I'm not sure what went wrong.. Thanks in advance

    (Ans=3.86s)
    Your time in air is correct, for some reason your time taken in the water is half the actual time taken. I'm not entirely sure what you've done, just use u=28 a=-56 s=0 and work out t to get the total time spent in the water.
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    (Original post by Jackasnacks)
    Massive apologies for the state of my work lol. Don't bother reading it if you don't want to!
    ive got part 1 of the Q regarding the distance (7m)
    but for the time surely it's the time taken to travel through the air (I got 20/7seconds) plus 2x the time taken from top of water to bottom of water

    but the answers wrong and I'm not sure what went wrong.. Thanks in advance

    (Ans=3.86s)
    You are right that your workings are a bit messy (I am a very neat writer)

    However I did the question and got 20/7 + 2 lots of 0.5 which gives 27/7 = 3.86 (3.f)

    there is probably a small numerical error somewhere
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    (Original post by Chlorophile)
    Your time in air is correct, for some reason your time taken in the water is half the actual time taken. I'm not entirely sure what you've done, just use u=28 a=-56 s=0 and work out t to get the total time spent in the water.

    (Original post by TeeEm)
    You are right that your workings are a bit messy (I am a very neat writer)

    However I did the question and got 20/7 + 2 lots of 0.5 which gives 27/7 = 3.86 (3.f)

    there is probably a small numerical error somewhere

    Probably messed it up somewhere I don't even know
    but using s=0 works so thanks very much!


    So done with mechanics
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    (Original post by iAmanze)
    Reserved.

    reserved?
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    (Original post by Jackasnacks)
    Probably messed it up somewhere I don't even know
    but using s=0 works so thanks very much!


    So done with mechanics


    no worries

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    (Original post by Jackasnacks)
    Massive apologies for the state of my work lol. Don't bother reading it if you don't want to!
    ive got part 1 of the Q regarding the distance (7m)
    but for the time surely it's the time taken to travel through the air (I got 20/7seconds) plus 2x the time taken from top of water to bottom of water

    but the answers wrong and I'm not sure what went wrong.. Thanks in advance

    (Ans=3.86s)
    Fixed my reserve. Answer is there (my first reply up above).
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    (Original post by iAmanze)
    Fixed my reserve. Answer is there (my first reply up above).
 
 
 
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