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    (Original post by TheFarmerLad)
    Having just consulted teachercol on the matter, he recommends leaving final answers to 2.s.f (unless the data is to three) and then for further calculations involving your previous answer, carry 3 s.f forward and then once again leave the overall final answer to two. I personally think that is a silly method - think it would make a lot more sense to carry exact answers forward from previous calculations and then always leave the final answer to 3 s.f. :mad:
    do you only leave to 3 sf if all the data given to 3sf? and yh i agree its stupid, they should make 3s.f the standard or at least be consistent in markschemes.
    Thanks for the help tho
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    (Original post by rm761)
    do you only leave to 3 sf if all the data given to 3sf? and yh i agree its stupid, they should make 3s.f the standard or at least be consistent in markschemes.
    Thanks for the help tho
    Yes. Whole physics exam is stupid tbh, too much emphasis on words and too little on maths!
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    Ive barely revised for this exam!!! I'm not as worried for this as for G485 but I just hope this doesn't go awfully.
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    (Original post by Aph)
    Ive barely revised for this exam!!! I'm not as worried for this as for G485 but I just hope this doesn't go awfully.
    trust me revise bare, i missed my uni offer cuz of this exam last yr cuz i thought it would be easy but since 2014 g484 been bare hard
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    anyone know if this still true (jan 2012 markscheme)Name:  temp 1.png
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    (Original post by TheFarmerLad)
    Yes. Whole physics exam is stupid tbh, too much emphasis on words and too little on maths!
    yeah that's why i hate revising physics the most. tad boring and not aligning much with real physics.
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    (Original post by rm761)
    anyone know if this still true (jan 2012 markscheme)Name:  temp 1.png
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    Should be, you'll never be penalised for too many s.f., unless they specifically tell you to give the answer to a certain amount or perhaps if you give it to like 10 s.f.
    They also say that they'll only dock 1 mark overall if you give too few s.f. but whether that means you can just lazily give everything to 1 s.f. and still get 59/60 I'm not too certain on.
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    Does anyone have the 2015 paper?
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    (Original post by Louisb19)
    Does anyone have the 2015 paper?
    Attached, with mark scheme
    Attached Images
  1. File Type: pdf G484-01 QP Jun15.pdf (472.5 KB, 131 views)
  2. File Type: pdf G484_MS_June15.pdf (588.5 KB, 122 views)
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    (Original post by Louisb19)
    Does anyone have the 2015 paper?
    Someone linked it, both G484/5, it was a googledrive link on page 3 or 4 I think.
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    Name:  image.png
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    Markscheme answer for assumption of ideal gases.
    What I'm confused about is they either use "particle" or "molecule".
    Are the 2 terms interchanging (for the purpose of this exam) or like is there a difference between them that like if you confuse then you could lose a mark??
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    Just done the 2014 paper and the most of my errors were due to the questions being ambiguously or just poorly worded. Anyone else had this problem or is my comprehension just bad? I accept it could easily be the latter and I need to do more past papers to get more familiar with how OCR word questions
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    Name:  13460778_1808939949334561_1741456060_o.jpg
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Size:  66.0 KBJune 2015 ques 2iv) The way i answered it is wrong because the markscheme says force delivered is constant (so in f=ma, acceleration increases and mass decreases to make F constant) but how Can I know F delivered is constant?? when Xe ions are ejected arn't the acceleration supposed to decrease as lesser net force in the first place??

    Thanks in advance
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    (Original post by Tajwar786)
    Name:  13460778_1808939949334561_1741456060_o.jpg
Views: 164
Size:  66.0 KBJune 2015 ques 2iv) The way i answered it is wrong because the markscheme says force delivered is constant (so in f=ma, acceleration increases and mass decreases to make F constant) but how Can I know F delivered is constant?? when Xe ions are ejected arn't the acceleration supposed to decrease as lesser net force in the first place??

    Thanks in advance
    The question says "The ions are ejected at a constant rate" so as the same amount of ions are ejected at all times, then the force exerted on the spacecraft as a result of ejecting ions will be the same. As it ejects more ions, the mass of the spacecraft will decrease but it will still continue ejecting the same number of ions each second so the force remains the same while mass decreases.

    (Original post by Siddhart1998)
    Name:  image.png
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    Markscheme answer for assumption of ideal gases.
    What I'm confused about is they either use "particle" or "molecule".
    Are the 2 terms interchanging (for the purpose of this exam) or like is there a difference between them that like if you confuse then you could lose a mark??
    I believe they are interchangeable for this exam but I tend to use molecule. If the question explicitly refers to particles or molecules then use the same word but otherwise I don't think it matters.
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    [QUOTE=PotAuFeu;65916330]The question says "The ions are ejected at a constant rate" so as the same amount of ions are ejected at all times, then the force exerted on the spacecraft as a result of ejecting ions will be the same. As it ejects more ions, the mass of the spacecraft will decrease but it will still continue ejecting the same number of ions each second so the force remains the same while mass decreases.


    Thank you so much for that I really need to pay attention to key details in the questions (I tend to avoid reading the intro most times :/, just pick out the numbers)
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    Could someone please explain (help me understand)

    Jan 2010 - Q3 - https://6d58568f77fa37b9c685ab8ce928...%20A-level.pdf

    "The ground is level. The ball leaves the ground at a velocity of 50 m s–1 at an angle of 42°to the horizontal. Determine the horizontal distance travelled by the ball before it hits theground.

    State one assumption that you make in your calculations."
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    (Original post by xenajada)
    Could someone please explain (help me understand)

    Jan 2010 - Q3 - https://6d58568f77fa37b9c685ab8ce928...%20A-level.pdf

    "The ground is level. The ball leaves the ground at a velocity of 50 m s–1 at an angle of 42°to the horizontal. Determine the horizontal distance travelled by the ball before it hits theground.

    State one assumption that you make in your calculations."
    First you want to split up the velocity into its vertical and horizontal components. We are assuming that there is no air resistance so the horizontal velocity will remain constant throughout its flight. x=vt (where v is the horizontal velocity), therefore we need to find the flight time (t) to find the horizontal distance travelled.
    To find flight time, use SUVAT equations with the vertical velocity to calculate time for the velocity to decrease to zero, this is half the flight time as it is the top of the 'flight parabola' (there's probably a more technical name). So double this to find the flight time and sub it into x=vt.
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    guys for 6ai, do i start the graph at +0.04m or -0.04m ? I'm not sure because in the question it says 'The aeroplane is pulled DOWN and released'

    The ms says cosine curve but it doesn't say where the graph starts, sorry if im being dumb
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  3. File Type: pdf 2005 June - Forces, Fields & Energy.pdf (363.7 KB, 153 views)
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    (Original post by Algeriandz)
    guys for 6ai, do i start the graph at +0.04m or -0.04m ? I'm not sure because in the question it says 'The aeroplane is pulled DOWN and released'

    The ms says cosine curve but it doesn't say where the graph starts, sorry if im being dumb
    Not 100% certain but I would say -0.04 as where it is released is its lowest point
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    Yeah it starts from 0.04, I think from +ve or -ve
 
 
 
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