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    Typically I will take a look at Section B and see how hard it looks. Lol.
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    (Original post by particlestudent)
    I honestly don't know which one to do first...
    with section A, you can give reasonable guesses and you'd have about 50% chance of getting it right because for some questions you can eliminate two obviously incorrect answers, so if you're stressed for time, section A is easier to rush through without compromising your mark too much

    section B has more marks per question and you should try to get it done first because its harder to guess those if you run out of time
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    (Original post by Nikulp68)
    There was a printing error in one of the questions; the capacitor one.
    Nope.


    AQA apologises for the unfortunate typographical error which crept in to the resistor values in part(a) of this question. Both values ought to have been given in kΩ. The majority of students actually answered the question as it had been intended to appear, and so the mark scheme that would have applied to the intended question in part (ii) was used when marking their work. The students who answered the question as it appeared in the paper were not disadvantaged, because an alternative mark scheme which gave full credit for completely correct responses was adopted for them.
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    (Original post by Pavinder100)
    Attachment 553052could someone explain to me how to answer part (ii) in the question

    I know that when you first turn it on there is a rate of change of magnetic flux linkage which = emf

    Since its a dc current the new change will occur and stay constant. which causes the pointer to deflect in one direction and back

    I believe that emf is felt in coil q and then since there is a circuit current is induced.
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    Obviously it's hard to predict but what do you guys think the 6 marker will be on? What would be an ideal topic/worst nightmare for you?

    Personally if it's capacitance I'll probably cry on the page and get more marks than I would writing anything
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    (Original post by Pavinder100)
    Attachment 553052could someone explain to me how to answer part (ii) in the question

    I know that when you first turn it on there is a rate of change of magnetic flux linkage which = emf

    Since its a dc current the new change will occur and stay constant. which causes the pointer to deflect in one direction and back


    I believe that emf is felt in coil q and then since there is a circuit current is induced.
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    (Original post by particlestudent)
    Is everyone doing Section B first?
    I just always do section A first by default
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    (Original post by Pavinder100)
    Attachment 553052could someone explain to me how to answer part (ii) in the question
    So you have a constant current and a constant magnetic field produced so no more EMF is produced after the initial burst (flux linkage is constant).

    When the resistance is decreased there is a reduction in current which reduces the strength of the magnetic field and therefore flux linkage.

    A reduction in flux linkage is a negative EMF.

    Therefore the ammeter reads negative temporarily.
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    (Original post by alevelstresss)
    with section A, you can give reasonable guesses and you'd have about 50% chance of getting it right because for some questions you can eliminate two obviously incorrect answers, so if you're stressed for time, section A is easier to rush through without compromising your mark too much

    section B has more marks per question and you should try to get it done first because its harder to guess those if you run out of time
    That's true. Normally from what I've noticed doing past papers, I can fly through the first like 1 to 7 questions on the MC part and (as well as the capacitors), it's the gravitational/electrical fields questions I get stuck on a lot.

    The user above you mentioned looking through B first to see how hard it looks, I may do that ...

    I hope there is barely anything on EM induction apart from transformers.
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    (Original post by mgill17)
    Obviously it's hard to predict but what do you guys think the 6 marker will be on? What would be an ideal topic/worst nightmare for you?

    Personally if it's capacitance I'll probably cry on the page and get more marks than I would writing anything
    I think it will be on gravitational fields or capacitors. I hope it's one of these .
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    (Original post by particlestudent)
    I think it will be on gravitational fields or capacitors. I hope it's one of these .
    I thought gravitation or potentially another mechanics one since there's so much you can ask in further mechanics.

    Please not capacitance, god no
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    Hopefully a practical on pendulums or capacitance will be a nice 6 marker.
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    Name:  ImageUploadedByStudent Room1466352392.511252.jpg
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    I understand why it flicks less but could someone please explain why it flicks in the opposite direction???


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    Is this right for EM induction. E.m.f. is induced in conductor, this induces a current which produces a magnetic field that opposes motion?


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    (Original post by rory58824)
    Hopefully a practical on pendulums or capacitance will be a nice 6 marker.
    Variable length? 8 values of length dropped at same amplitude? T measured (3 and average). Plot T^2 v l?


    Posted from TSR Mobile
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    (Original post by Yo12345)
    Variable length? 8 values of length dropped at same amplitude? T measured (3 and average). Plot T^2 v l?


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    Yep, anything like that would be great but I doubt it, as on of the ISA's was based on it so they may feel a lot of people will score highly on it.
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    (Original post by Yo12345)
    Is this right for EM induction. E.m.f. is induced in conductor, this induces a current which produces a magnetic field that opposes motion?


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    Thats seem right, you could score more marks if you include Faradays law and Lenz law
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    What did people think of the UMS for ISAs this year? Same as last year? I got 47/50 and was wondering if that would be 54 UMS like last year, more, or less, so I can help work out what I need for an A
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    (Original post by Cheesecake Ali)
    Name:  ImageUploadedByStudent Room1466352392.511252.jpg
Views: 88
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    I understand why it flicks less but could someone please explain why it flicks in the opposite direction???


    Posted from TSR Mobile
    When the resistance increases, the current in the primary coil decreases, causing the magnetic flux passing through the secondary coil to be reduced. This change in flux causes an EMF to be induced in the other direction because the field is moving in the opposite direction to before.

    It's not actually possible to say that it "flicks less" as you don't know how quickly the resistance of the variable resistor was increased.
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    (Original post by Cheesecake Ali)
    Name:  ImageUploadedByStudent Room1466352392.511252.jpg
Views: 88
Size:  129.5 KB
    I understand why it flicks less but could someone please explain why it flicks in the opposite direction???


    Posted from TSR Mobile
    It doesn't actually deflect less you can't know that without knowing the speed at which the slider was being moved each time.

    It is in the opposite direction because while S is still closed and the resistance is reduced there is a rate of change in flux linkage but the emf is induced in the other direction (loosely speaking) so the ammeter deflects the other way
 
 
 
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