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    (Original post by TSRPAV)
    kinda, basically if you resolve horizontally in this "theory" without air resistance there is no resistive forces to decelerate(slow it down) and it will not be accelerating as there is no thrust proving acceleration(no overall force as no acceleration so only v=s/t applies)so we use the impulse velocity, which is what it is travelling as it left the racket and as the time of horizontal and vertical displacement is the same/constant (read about monkey-hunter model) we can use v=s/t so v is proportional to s (as t is constant).so basically all values are max

    When air resistance occurs in practice horizontally: the time to displace horizontally and vertically is still the same(constant) however there is a resistive drag force on the ball which causes it to decelerate, as there is no thrust on the ball after it has left the racket the only horizontal force acting on it is the air resistance which will be large and slowly decrease(decelerate the ball) until zero when it no longer moves horizontally So as the ball is decelerating its mean velocity is less. so v=s/t (where t is constant) if v decreases, t is constant then s must decrease
    philo-jitsuthanks guys, appreciate the help
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    (Original post by TSRPAV)
    not much, done like 6 of the papers and i do maths mechanics which helpsish
    So u think they can't ask much different from past papers? Worried they might ask something not seen on a past paper and I'll fail it
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    (Original post by ryandaniels2015)
    Thanks I understand, so then why does it matter if u use 3m or 50m for distance?
    He hasnt travelled 3M, ...think in triangles, 50m is the resultant distance. so the 50m is already accounting for the 3m. it accounts for the horizontal distance and the 3m vertically
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    Ok, Thanks! that makes sense
    (Original post by philo-jitsu)
    He hasnt travelled 3M, ...think in triangles, 50m is the resultant distance. so the 50m is already accounting for the 3m. it accounts for the horizontal distance and the 3m vertically
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    (Original post by TSRPAV)
    not much, done like 6 of the papers and i do maths mechanics which helpsish
    Howd you find M1.....mine did not go great....lots of really dumb errors....the only redeeming quality is that I made so many dumb errors I think I'm all out for the rest of the exams.....its plain sailing from here on in .... :-)
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    (Original post by ryandaniels2015)
    So u think they can't ask much different from past papers? Worried they might ask something not seen on a past paper and I'll fail it
    yeh man i kno- tbf i barley know much of this unit, just think about basic principles and BS it, also equation sheet helps ALOT, you can derive units,define what things are and test out the effect of changing varibles by putting numbers into equations to see what effect they have on thing you want e.g how does a smaller wavelength effect the finge spacing> or e.g whats hookes law?; on dta sheet it says F=k*e so if k is a constant then f must be proportional to e ect. just have a got at small things like that,they are useful- i dunno man im just gunna wing it and pray
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    I will try to remember as many questions as possible tomorrow....hopefully we can formulate an unofficial mark scheme....physics answers are relatively straight forward so it should be doable
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    (Original post by philo-jitsu)
    Howd you find M1.....mine did not go great....lots of really dumb errors....the only redeeming quality is that I made so many dumb errors I think I'm all out for the rest of the exams.....its plain sailing from here on in .... :-)
    ahah same man m1 was messy this year :/ i made so many stupid small mistakes but my biggest were on the impulse question i got everything (method right) but i got the deceleration wrong cos i forgot to divide by 0.4 such a rookie error aha hopefully will only lose 2 marks max cos it it, also the 7a) vectors i couldn't finish off so lost almost all the marks on that question. You doing c3/c4?
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    wounder how many people will sit this exam
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    (Original post by philo-jitsu)
    I will try to remember as many questions as possible tomorrow....hopefully we can formulate an unofficial mark scheme....physics answers are relatively straight forward so it should be doable
    Yhh same. I did ask if there would be a sort of unofficial mark scheme, but I dont think anyone knew.
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    There wont be any unofficial markscheme from anyone else except us as this is old spec and not many people will sit it
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    (Original post by TSRPAV)
    ahah same man m1 was messy this year :/ i made so many stupid small mistakes but my biggest were on the impulse question i got everything (method right) but i got the deceleration wrong cos i forgot to divide by 0.4 such a rookie error aha hopefully will only lose 2 marks max cos it it, also the 7a) vectors i couldn't finish off so lost almost all the marks on that question. You doing c3/c4?
    Yeah, oddly enough im way more confident about them...and yeah I did the opposite, I got the impulse and simultaneous equation vector equation, but I messed up the speed time graph question, and the last question I did the first equation right but for the vertical side of the pulley I put T as positive instead of negative......so many ways to mess up on M1....its infuriating

    and I messed up the moments question, and I got the wrong distance...used 6m instead of 4m....such a dumb mistake!!

    pretty much need 95ums in both c3&4....so no pressure!!
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    (Original post by philo-jitsu)
    Yeah, oddly enough im way more confident about them...and yeah I did the opposite, I got the impulse and simultaneous equation vector equation, but I messed up the speed time graph question, and the last question I did the first equation right but for the vertical side of the pulley I put T as positive instead of negative......so many ways to mess up on M1....its infuriating

    and I messed up the moments question, and I got the wrong distance...used 6m instead of 4m....such a dumb mistake!!

    pretty much need 95ums in both c3&4....so no pressure!!
    ahaha how weird im the exact same! been getting 90-100 ums in practice for c3 from dec/jan and now c4 is finally to the 90ums+ (oddly c4 is easier than c3 but easy to lose chunks of marks by one small mistake) anyway when it comes to exams my perfomance normally drops ((, i got moments right for distance but messed up the mass somehow aha, yeah the last question was funny cos i got it but i swear i wrote so little for so many marks, ah man the resolving is a pain, you should get error carried for part on on the pulley.
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    (Original post by philo-jitsu)
    Yeah, oddly enough im way more confident about them...and yeah I did the opposite, I got the impulse and simultaneous equation vector equation, but I messed up the speed time graph question, and the last question I did the first equation right but for the vertical side of the pulley I put T as positive instead of negative......so many ways to mess up on M1....its infuriating

    and I messed up the moments question, and I got the wrong distance...used 6m instead of 4m....such a dumb mistake!!

    pretty much need 95ums in both c3&4....so no pressure!!
    You appling to uni/what course?
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    Never knew longitudinal waves can superpose until June14 paper lol
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    (Original post by philo-jitsu)
    Howd you find M1.....mine did not go great....lots of really dumb errors....the only redeeming quality is that I made so many dumb errors I think I'm all out for the rest of the exams.....its plain sailing from here on in .... :-)
    M1 was fine made a silly mistake on the vector question. Lol and also sat FP2, which alot of people complained about
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    http://www.cram.com/flashcards/phya2-7307000
    Btw guys I don't have everything on here but it's how much I've collected so far
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    How do you do q.4 (c)(i) June 2014


    Because surely  \Delta L = 0.24*1.5 = 0.36 so therefore \frac{\Delta L}{L} = \frac{0.36}{1.5} = 0.24

    What am I doing wrong?
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    (Original post by Music With Rocks)
    How do you do q.4 (c)(i) June 2014


    Because surely  \Delta L = 0.24*1.5 = 0.36 so therefore \frac{\Delta L}{L} = \frac{0.36}{1.5} = 0.24

    What am I doing wrong?
    The question is asking for stress not strain
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    (Original post by ryandaniels2015)
    The question is asking for stress not strain
    Yeah but you need the strain first, it is the first part of the working if you look at the mark scheme above
 
 
 
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