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2016 | OCR A2 Advancing Physics B | G494 & G495 | 20th & 28th June watch

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    (Original post by cam5morrison)
    Boundary predictions? A* around 50 ish maybe idk
    Hard to say. 50 is quite high as G494 papers go (the highest I've seen is 51), and I wouldn't say that this was an exceptionally easy paper. It was fairly standard.

    My guess would be 47.
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    Question 9 I worked out rc from initial tangent, then subbed it and a value of the graph in to q0e-t/rc, is this enough for a proof as it only did one point?
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    For the relativistic one, I used 2x10^8 as the value for velocity which meant gamma factor was 1.34 instead of 1.25 as I wasn't sure whether my initial calculated one was right. This then gave me a time of 3.73 not 4ns. Would I still get the marks??
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    As someone consistently turd at physics, I found that paper surprisingly good!
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    (Original post by AlexM10)
    For the relativistic one, I used 2x10^8 as the value for velocity which meant gamma factor was 1.34 instead of 1.25 as I wasn't sure whether my initial calculated one was right. This then gave me a time of 3.73 not 4ns. Would I still get the marks??
    Yup.
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    (Original post by AlexM10)
    For the relativistic one, I used 2x10^8 as the value for velocity which meant gamma factor was 1.34 instead of 1.25 as I wasn't sure whether my initial calculated one was right. This then gave me a time of 3.73 not 4ns. Would I still get the marks??
    I got 4.0 ns, but I'd imagine both answers will be fully creditted if the method is sound - past mark schemes often accept a wide range of final answers given the possible source data come that point in a question.

    The use of a show-that is often so students can still have access to later marks, given in theory perhaps a candidate may have been unable to attempt the first part of a question at all. That is, the paper is designed such that lack of knowledge/inability in part (a) is not punished by locking away marks in subseuqent parts of the question.

    I'm 99% sure your answer will be good, too, basically.
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    (Original post by stokes97)
    Question 9 I worked out rc from initial tangent, then subbed it and a value of the graph in to q0e-t/rc, is this enough for a proof as it only did one point?
    Probably not, I'm afraid.
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    Thanks both for the replies, put my mind at rest!!
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    Hello! I was pretty disappointed in myself in this paper cos when doing past papers I kept getting like As and in this paper I doubt I got that here. Hopefully...HOPEFULLY I get above 40 in this paper at least. I hated the vacuum question, I just left out the last part. Sigh...
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    (Original post by stokes97)
    Question 9 I worked out rc from initial tangent, then subbed it and a value of the graph in to q0e-t/rc, is this enough for a proof as it only did one point?
    I did a similar thing, I knew that R and C around the circuit wouldn't change since the circuit wasn't altered part way through. I then used the equation V=V0e^-t/RC and rearranged to find RC at two different points along the graph. The values I got were not the same therefore RC didn't stay constant and I said this meant it wasn't exponential decay.

    I have no idea if this is the ideal answer/will be reflected in the mark scheme
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    (Original post by irrationalvarun)
    Hello! I was pretty disappointed in myself in this paper cos when doing past papers I kept getting like As and in this paper I doubt I got that here. Hopefully...HOPEFULLY I get above 40 in this paper at least. I hated the vacuum question, I just left out the last part. Sigh...
    The vacuum question was a bit awkward. I know I fell short at the uncertainty part, like many did, but the rest of it was okay I think. It just felt uncomfortable because equilibrium is something we usually do in terms of force, rather than pressure, but s'all the same I guess. The description bit just required the hurling of terminology at the paper; something something collision, something something exchange of momentum, something something rate of change of blah blah equals force, etc.

    It was made-up for by a really simple final question, methinks.
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    (Original post by Funwithphysics)
    I did a similar thing, I knew that R and C around the circuit wouldn't change since the circuit wasn't altered part way through. I then used the equation V=V0e^-t/RC and rearranged to find RC at two different points along the graph. The values I got were not the same therefore RC didn't stay constant and I said this meant it wasn't exponential decay.

    I have no idea if this is the ideal answer/will be reflected in the mark scheme
    If you took two points and showed that RC had changed, I think you nailed it m80.
    I just did the half-life ting though. :awesome: timeismunni
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    (Original post by WhiteBison)
    The vacuum question was a bit awkward. I know I fell short at the uncertainty part, like many did, but the rest of it was okay I think. It just felt uncomfortable because equilibrium is something we usually do in terms of force, rather than pressure, but s'all the same I guess. The description bit just required the hurling of terminology at the paper; something something collision, something something exchange of momentum, something something rate of change of blah blah equals force, etc.

    It was made-up for by a really simple final question, methinks.
    I know right? And for the last part most people I know just wrote down the area for the 30mm diameter then left it there. Also a lot of people also misread and took the diameter in the calculation as the radius. Usually I'm dreadful at explanations and great at calculations, but it was actually the opposite in this case.
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    (Original post by irrationalvarun)
    I know right? And for the last part most people I know just wrote down the area for the 30mm diameter then left it there. Also a lot of people also misread and took the diameter in the calculation as the radius. Usually I'm dreadful at explanations and great at calculations, but it was actually the opposite in this case.
    Yeah I wouldn't worry too much about it. It's just the lil' stuff like this why it's so much harder to get 100% in Physics than say a Maths module. S'all gooood.

    Anyways, better get back to work revisiong for the exam tomorrow.
    /goodbye until G495 :hoppy:
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    (Original post by M12345689)
    i think you had to take that away from the 100kpa atmospheric pressure
    Yeahh I got 83kPa, resolved forces for it lmao
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    (Original post by WhiteBison)
    Yeah I wouldn't worry too much about it. It's just the lil' stuff like this why it's so much harder to get 100% in Physics than say a Maths module. S'all gooood.

    Anyways, better get back to work revisiong for the exam tomorrow.
    /goodbye until G495 :hoppy:
    Bye! And good luck with what exam you're having! (I'm having C3 tomorrow so I'm not at all worried about it)
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    (Original post by senots)
    Yeahh I got 83kPa, resolved forces for it lmao
    I concur.
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    (Original post by Mik3yMcFly001)
    I concur.
    As do I
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    Literally so annoyed at myself because for the life of me couldn't work out how I got the pressure wrong on the vacuum question. Now realised I used 12m rather than 12mm diameter, which explains my right answer, just not to the right power😩😩😩
    So annoyed at myself!!
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    I got 170000pa too or 17000pa I cant remember
    (Original post by smartalan73)
    I got about 170000 Pa??
 
 
 

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