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    (Original post by Student403)
    Yeah that irritated me so much. I kept writing 1/2 mv^2... mgh.. then realising I had to stick a stupid 2 in there
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    lol yep my friend showed me that question after he came out and he missed the 2m from the "mv^2/r" term hence he got like 5l/8 instead of l/2 or whatever it was. He also showed me the last question (if that was the shm one) where the two particles coalesce. He tried showing max. Ek was conserved which made sense but he ended up with the same amplitude as before so idk if there was an algebraic slip or something.
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    (Original post by Insight314)
    I think it would be way lower. TSR does not represent how most people found the exam, and 6 b) would've caught quite a few people off.
    I feel like that won't be the case for M4/5, but are there many people who took M3 and aren't TSR addicts?

    Since 2009, the average mark for an A is 60.6, and 67.7 for an A*. It's hard to predict the boundary this year, because even though most of the paper was straight-forward, I have no idea what the average mark will be for the 9 mark question.
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    (Original post by EnglishMuon)
    Spoiler just in case we're not suppose to discuss for some reason
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    lol yep my friend showed me that question after he came out and he missed the 2m from the "mv^2/r" term hence he got like 5l/8 instead of l/2 or whatever it was. He also showed me the last question (if that was the shm one) where the two particles coalesce. He tried showing max. Ek was conserved which made sense but he ended up with the same amplitude as before so idk if there was an algebraic slip or something.
    Since it's afternoon in the UK and this was a morning paper, I think we're fine now. But unlucky for your friend :/
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    (Original post by Student403)
    Yeah that irritated me so much. I kept writing 1/2 mv^2... mgh.. then realising I had to stick a stupid 2 in there

    Yeah! From what I remember though, all 2m's were cancelled in the end so it actually didn't matter, right?
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    (Original post by Student403)
    Yeah that irritated me so much. I kept writing 1/2 mv^2... mgh.. then realising I had to stick a stupid 2 in there
    The same here, fortunately still got all ok lol , it has nothing to do with the maths, it is just there to let us down =.=
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    (Original post by EnglishMuon)
    Spoiler just in case we're not suppose to discuss for some reason
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    lol yep my friend showed me that question after he came out and he missed the 2m from the "mv^2/r" term hence he got like 5l/8 instead of l/2 or whatever it was. He also showed me the last question (if that was the shm one) where the two particles coalesce. He tried showing max. Ek was conserved which made sense but he ended up with the same amplitude as before so idk if there was an algebraic slip or something.
    Lol. I got the same mistake as your friend but then went back to correct it and got the final answer right.

    How was the exam m8?


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    (Original post by physicsmaths)
    Do -T=(newmass)a
    That was it, it was only 3 marks.


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    (Original post by oShahpo)
    Yea exactly as I did 100% UMS then if I didn't misround any of the answers.
    (Original post by Insight314)
    I was actually baffled at how easy it was. Probably caught out a few people, I am not joking. I was scared that I got it wrong lol.


    Posted from TSR Mobile
    I did almost exactly the same, but I had the minus sign on the acceleration side first then moved it to the x side.
    Also, I used x with two dots on top instead of the symbol "a" for my acceleration as I used the symbol "a" later for amplitude.

    Do you think either of these will drop marks, given that in the end I proved it correctly albeit with xdoubledot instead of a?
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    (Original post by pinksmartiee)
    Yeah! From what I remember though, all 2m's were cancelled in the end so it actually didn't matter, right?
    I think so I remember all the ms factor out in your expression [something] > 0 where Tension = [something]
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    (Original post by Maths2002)
    Hey guys did you notice that the mass of the particle is 2m(not m) in question 6??
    I made this mistake waaaay too many times in past papers to make it in the exam
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    (Original post by themechguy)
    I did almost exactly the same, but I had the minus sign on the acceleration side first then moved it to the x side.
    Also, I used x with two dots on top instead of the symbol "a" for my acceleration as I used the symbol "a" later for amplitude.

    Do you think either of these will drop marks, given that in the end I proved it correctly albeit with xdoubledot instead of a?
    If this is for SHM then x-double-dot is correct. I've seen mark schemes say that using "a" instead loses a mark.
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    (Original post by Student403)
    I think so I remember all the ms factor out in your expression [something] > 0 where Tension = [something]
    yupppp agreed.
    I just didn't like the last part of the last question.. Getting the amplitude of the new shm. I somehow got 1.something.. which is larger than the original 0.8m I'm just waiting for somebody's model answers :P
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    (Original post by themechguy)
    I did almost exactly the same, but I had the minus sign on the acceleration side first then moved it to the x side.
    Also, I used x with two dots on top instead of the symbol "a" for my acceleration as I used the symbol "a" later for amplitude.

    Do you think either of these will drop marks, given that in the end I proved it correctly albeit with xdoubledot instead of a?
    A previous report said that "students failed to use xdotdot for acceleration" so I imagine using xdotdot is correct, which is what I did.
    I wouldn't imagine you'd lose marks for putting the negative on the acceleration side. Fnet = -T is the same as T = -Fnet.
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    Cast a vote and see last year's vote and actual boundaries

    http://www.thestudentroom.co.uk/show....php?t=4094789
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    (Original post by pinksmartiee)
    yupppp agreed.
    I just didn't like the last part of the last question.. Getting the amplitude of the new shm. I somehow got 1.something.. which is larger than the original 0.8m I'm just waiting for somebody's model answers :P
    You use momentum to find the new velocity, then use that alongside your w to find the new a.
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    Looks like I'm the only one who ****ed it up
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    (Original post by Foutre en L'air)
    Looks like I'm the only one who ****ed it up
    How badly?
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    (Original post by pinksmartiee)
    yupppp agreed.
    I just didn't like the last part of the last question.. Getting the amplitude of the new shm. I somehow got 1.something.. which is larger than the original 0.8m I'm just waiting for somebody's model answers :P
    Unlucky :/ Nice thing about mechanics is all the method marks you can pick up
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    (Original post by Foutre en L'air)
    Looks like I'm the only one who ****ed it up
    People who screwed up are unlikely to comment about it, so don't worry.
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    (Original post by Foutre en L'air)
    Looks like I'm the only one who ****ed it up
    What makes you think it went badly? I'm sure it's not as bad as you think

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    If you write down two answers, one which is correct and the other incorrect. Do examiners ignore the incorrect answer and still give the marks?
 
 
 
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