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EDEXCEL A2 Physics EXAM Unit 4 Physics On The Move 20th June 2016 (NOT I-A-L) Watch

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    (Original post by jtebbbs)
    Yeah I was 100% convinced it was 17% but now I'm not so sure, there's no denying that if you're at 2.8mm you could go to 4.2 which would be a 33% decrease like you say. Hopefully Edexcel will accept either because of the ambiguity of the question. I did all the working for 33% then crossed it out and did it for 17%
    Haha. I am yours inverse
    I give out 17% initially
    Then I felt like I need to put 33.3%😂
    Yea hopefully themed exdexcel will allow
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    Im sure the question asked for max % difference in charge and not distance or displacement so 17% and 33% would be wrong
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    (Original post by ajaxkiller)
    also did you get 20% for max?
    I got 20% aswell
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    (Original post by Ilaawef)
    One of the questions was about why the silicon plate had such a small capacitance, anyone remember what they answered for that?
    (Original post by funkyfig)
    I said that it was to do with the time constant (RC) needing to be low but I'm not sure if that is correct?
    (Original post by oShahpo)
    small rc so discharges quickly, also holds less charge so more sensitive.
    (Original post by Ilaawef)
    I'm not sure myself, I didn't actually get to answer it because it was confusing. All I remember was the question stating it needs to detect minute changes in the distance. Probably because silicon is used in sensitive circuits?
    Oh no... I really don't remember that question, I'm worrying that I didn't answer it now... Do any of you remember the exact question or how many marks it was worth?
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    (Original post by EmmaLouise759)
    Oh no... I really don't remember that question, I'm worrying that I didn't answer it now... Do any of you remember the exact question or how many marks it was worth?
    It was a 6 marker...
    just kidding it was only 2 marks and it was about the effect of moving the capacitor or something of the sort.
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    (Original post by Freddielow)
    Its lower as V=angular velocity x radius and not fully inflater tyre means radius is smaller
    This is not correct. The speedometer was on a spoke - hence the deflating of the type would not decrease the radius and hence the angular velocity would not change. Since angular velocity and radius are constant the reading on the speedometer won't change.
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    (Original post by therussianhammer)
    I got 20% aswell
    nice but only me and you have this and everyone else is saying 17 or 33??
    so i think we might be wrong :/
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    (Original post by HelloWorld23)
    This is not correct. The speedometer was on a spoke - hence the deflating of the type would not decrease the radius and hence the angular velocity would not change. Since angular velocity and radius are constant the reading on the speedometer won't change.
    so writing no difference seen will get you the marks??
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    (Original post by HelloWorld23)
    This is not correct. The speedometer was on a spoke - hence the deflating of the type would not decrease the radius and hence the angular velocity would not change. Since angular velocity and radius are constant the reading on the speedometer won't change.
    That is true, but the value will actually be exaggerated as the actual radius of the tyre is decreased.
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    (Original post by ajaxkiller)
    nice but only me and you have this and everyone else is saying 17 or 33??
    so i think we might be wrong :/
    % difference is (initial value - final value) / initial value, which is what we did.

    Im still confident we were right despite the odds ahahaha
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    (Original post by therussianhammer)
    % difference is (initial value - final value) / initial value, which is what we did.

    Im still confident we were right despite the odds ahahaha
    that is true, we got a nice neat answer and these lot got some random rational number so probably :/
 
 
 
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