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    (Original post by Droneon)
    I thought it was really good. Except I made a few stupid mistakes. *facepalm*
    how did u calculate Emf and r from the graph?
    i wasnt sure i did that correct..
    and the last question.. what did u write for the protractor part?
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    (Original post by Droneon)
    I thought it was really good. Except I made a few stupid mistakes. *facepalm*
    Same! When I opened the paper I was like 🤔okay? Let's keep going
    Then the theory was decent but silly upon silly mistakes.
    The last question was absolutely atrocious
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    (Original post by Ddde)
    Same! When I opened the paper I was like 🤔okay? Let's keep going
    Then the theory was decent but silly upon silly mistakes.
    The last question was absolutely atrocious
    agreed.. i didnt really know what they expected us to write.. :/
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    (Original post by zooshan)
    how did u calculate Emf and r from the graph?
    i wasnt sure i did that correct..
    and the last question.. what did u write for the protractor part?
    Emf is the y intercept so 6V
    And r is the magnitude of the gradient, so it's 4, not -4
    Around that range for both answers

    In the protractor question, it was quite simple
    First of all, you use 20 degrees as you angle of incidence, then you use the refractive indexes for both zircon and diamond, get the angle of refraction
    It'll be 8.14 and 9.86 (something like that I don't remember exactly)
    Then you say
    'You won't be able to distinguish, because the division scale on the protractor +-1, so They may overlap
    I think if you use +-0.5 in your scale of the protractor and state otherwise, it's still be correct
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    (Original post by Yousifwithani)
    Emf is the y intercept so 6V
    And r is the magnitude of the gradient, so it's 4, not -4
    Around that range for both answers

    In the protractor question, it was quite simple
    First of all, you use 20 degrees as you angle of incidence, then you use the refractive indexes for both zircon and diamond, get the angle of refraction
    It'll be 8.14 and 9.86 (something like that I don't remember exactly)
    Then you say
    'You won't be able to distinguish, because the division scale on the protractor +-1, so They may overlap
    I think if you use +-0.5 in your scale of the protractor and state otherwise, it's still be correct
    then the emf is fine..
    the refractive indexes cant be that high.. the highest is for diamond which is 2.3
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    (Original post by zooshan)
    how did u calculate Emf and r from the graph?
    i wasnt sure i did that correct..
    and the last question.. what did u write for the protractor part?
    i coukldnt do that emf and r question by looking at the graph arghhh
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    (Original post by Shadowfire123)
    i coukldnt do that emf and r question by looking at the graph arghhh
    i did some silly mistakes all around...
    oh what about the 5 mark frequency sound intensity graph question?

    i think i wrote the points all wrong
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    (Original post by zooshan)
    then the emf is fine..
    the refractive indexes cant be that high.. the highest is for diamond which is 2.3
    Those values aren't the refractive index buddy, those are the angles of refraction
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    (Original post by Yousifwithani)
    Those values aren't the refractive index buddy, those are the angles of refraction
    ooh.. how did u get those values?
    thats not what i got..
    i did a bit of a different method, using the Pythagoras theorem and some other stuff :/
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    (Original post by zooshan)
    i did some silly mistakes all around...
    oh what about the 5 mark frequency sound intensity graph question?

    i think i wrote the points all wrong
    You have to talk about diffraction, you need to mention the following points
    • As the frequency of the sound increases, the intensity is constant for the left ear, but decreases for the right ear
    • as the frequency increases, the wavelength decreases
    • so the effect of diffraction is reduced
    • because diffraction is maximised when the size of the obstacle is approximately the size of the wavelength
    • so there's less spreading out of the wave
    • so less waves reach the right ear
    •causing a decrease in the intensity
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    (Original post by zooshan)
    ooh.. how did u get those values?
    thats not what i got..
    i did a bit of a different method, using the Pythagoras theorem and some other stuff :/
    Basically the question said 'using this, would you be able to distinguish between diamond and zircon
    So you already have the refractive index
    2.4 for diamond and 2 for zircon
    You have the angle of incidence which is 20 degrees, you use the snell's law
    n=sin I/sin r
    You obtain the values of r for both zircon and diamond and compare if you would be able to distinguish or not
    They gave you a hint in the question saying a protractor, so your answer needs to be an angle
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    (Original post by Yousifwithani)
    You have to talk about diffraction, you need to mention the following points
    • As the frequency of the sound increases, the intensity is constant for the left ear, but decreases for the right ear
    • as the frequency increases, the wavelength decreases
    • so the effect of diffraction is reduced
    • because diffraction is maximised when the size of the obstacle is approximately the size of the wavelength
    • so there's less spreading out of the wave
    • so less waves reach the right ear
    •causing a decrease in the intensity
    so i wont get full marks for that question.. i think...
    what about which polarized filter the fisherman should use?
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    (Original post by zooshan)
    so i wont get full marks for that question.. i think...
    what about which polarized filter the fisherman should use?
    They said its parallel to the surface of the water, so it's horizontal, so you have to choose A because it's 90 degrees to the plane of polarisation, so the glare is blocked
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    (Original post by Yousifwithani)
    Basically the question said 'using this, would you be able to distinguish between diamond and zircon
    So you already have the refractive index
    2.4 for diamond and 2 for zircon
    You have the angle of incidence which is 20 degrees, you use the snell's law
    n=sin I/sin r
    You obtain the values of r for both zircon and diamond and compare if you would be able to distinguish or not
    They gave you a hint in the question saying a protractor, so your answer needs to be an angle
    well.. i used all of that..
    and the protractor to measure the refractive angle.. by 90-x..
    hmm.. will probably lose those marks.. rest of the paper was fine i think..is there an unofficial MS yet?
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    (Original post by Yousifwithani)
    They said its parallel to the surface of the water, so it's horizontal, so you have to choose A because it's 90 degrees to the plane of polarisation, so the glare is blocked
    yup.. it A..
    what do u think of the grade boundaires..
    50-55 for an A??
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    (Original post by Yousifwithani)
    They said its parallel to the surface of the water, so it's horizontal, so you have to choose A because it's 90 degrees to the plane of polarisation, so the glare is blocked
    That question bugged me because the position of the man is unknown, who knows if he was standing opposite the wave travel or something
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    (Original post by zooshan)
    well.. i used all of that..
    and the protractor to measure the refractive angle.. by 90-x..
    hmm.. will probably lose those marks.. rest of the paper was fine i think..is there an unofficial MS yet?
    Unofficial marking scheme usually takes a longer time to come out, Dw, the exam wasn't easy, you'll do just fine
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    (Original post by zooshan)
    yup.. it A..
    what do u think of the grade boundaires..
    50-55 for an A??
    I expect it to be around 54-57
    This was as challenging as Oct 16 and June 14 IAL
    so it should be around that area
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    (Original post by Ddde)
    That question bugged me because the position of the man is unknown, who knows if he was standing opposite the wave travel or something
    Dude I swear to god, I had no idea which one was which so I just chose it randomly
    I want to get an A in the paper so I chose A
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    (Original post by Yousifwithani)
    Unofficial marking scheme usually takes a longer time to come out, Dw, the exam wasn't easy, you'll do just fine
    What do you think the boundary will be for full UMS? 70 or less than that?
 
 
 
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