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    (Original post by bred123)
    woudnt the last question involve a phase shift, so a extra constant in the sin bracket since it didnt start at the extreme extension?

    i got the amp and other things wrong so il only get about 6 marks total for last question but im pretty sure you needed a phase shift,and im pretty sure it was the first time its ever came up on ocr
    It came up recently 14 I think, component falls under gravity plus shm stuff if that's what you meant by phase shift?


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    when you get a particle in SHM you use the cos or sin equations but thats only if there motion starts at the amplitude or the center. this one started in between them 2 though, so would the equation be x=Asin(wt + p) where p is a phase shift translation that moves the graph of its motion back to the normal sin curve so you can do all your usual calculations with the sin graph.
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    Like that but the red one wouldnt be that far translated, it would be the brown one moved to the right slightly. so youl need a translation constant to get it back to the sin curve
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    i just realised you could start the motion model when it is at the bottom so there is no need for a phase shift wow im so sad. so glad that m2 was a good exam
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    Just worth noting that the January 2008 paper was roughly 88% raw for 100 UMS. I reckon this was a much harder paper.
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    (Original post by bred123)
    when you get a particle in SHM you use the cos or sin equations but thats only if there motion starts at the amplitude or the center. this one started in between them 2 though, so would the equation be x=Asin(wt + p) where p is a phase shift translation that moves the graph of its motion back to the normal sin curve so you can do all your usual calculations with the sin graph.
    Oh I see what you mean, usually refer to it as some offset epsilon, so it threw me off


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    (Original post by JoeyTr)
    I know this probably sounds weird but how did everyone's classmates find it? I was the only person doing it at my school so didn't really get the perspective. I don't really think people on the StudentRoom is a fair sample of how difficult people found the paper generally haha!
    Personally, I found it harder than all papers between 2005 and 2015. I still managed to solve it, but two SILLLLLLLYYYYY mistakes made me lose around 5~6 marks I guess....
    My peers found it hard too, and some did not even finish the paper....
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    Can someone recall question 7 part (iii) please. I think I got a=-10x rather than a=-10gx !!! :'(

    Also question 5 (part 1) would be helpful
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    Just found out I lost around 10 marks max... giving me 62/72....
    Btw, did you guys know that for 7(iv), Amplitude is larger than distance between Equilibrium position and point of natural length, so need to use suvat again....
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    (Original post by Mandos)
    Can someone recall question 7 part (iii) please. I think I got a=-10x rather than a=-10gx !!! :'(

    Also question 5 (part 1) would be helpful
    I got -40.....
    5.i, it was mg(2-3cos()) and height was 5/3 a
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    (Original post by cam5morrison)
    Just worth noting that the January 2008 paper was roughly 88% raw for 100 UMS. I reckon this was a much harder paper.
    I agree. In fact, I thought it was harder than any paper between 2005 and 2015
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    I made the same mistake as you, and got a=-40gx, but I realise now that when you equate tension-weight=ma (or something like that) your m in ma, is actually 4m, since it's a given quantity from the particles coalescing to have mass 4m. I just wrote ma and didn't think about it...

    (Original post by JxK^2)
    I got -40.....
    5.i, it was mg(2-3cos()) and height was 5/3 a
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    (Original post by JxK^2)
    I got -40.....
    5.i, it was mg(2-3cos()) and height was 5/3 a
    I got -40g lol
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    Anyone here doing M4 as well?
 
 
 
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