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    (Original post by Examguy123)
    Do you think they will allow 3.4? Like for rounding and stuff?
    Possibly. It might be the right answer anyway.
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    (Original post by JamieP123)
    Okay i'll try and explain that heater question.

    Firstly you consider the wires to have NO resistance therefore the power of the heater is simply V^2/R

    this is 230^2/12 = 4408 = 4400

    After this it tells you that in reality the cables will have an internal resistance

    You can consider the two wires as resistors (each with 3.15 * 0.0150 ohms of resistance = 0.04725) and place these in series with the 12 ohm resistor (heating element)

    the terminal voltage was 230 volts meaning that the voltage would be shared (as a potential divider) between the three different resistors.

    this means the voltage across the heating element would be (12/12+3.15*2*0.0150)*230. In other words, the resistance of the heating element over the total resistance of the circuit multiplied by the voltage. This gave 228.2029021 volts.

    The energy wasted in the two wires would be as follows: 230-228.2029021 = 1.797...= voltage shared between two cables. One cables voltage =1.797/2 = 0.8985...V^2/R again = 0.8985^2/0.04725 * 2 (there are two cables) = 34.1 W

    Im sure the resistance of the wires was in parallel not series ?
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    (Original post by beanigger)
    i know for a fact that X was a pi nought for 3 marks, i doubt you can get 3 marks for kaon nought because strangeness doesnt need to be conserved in that interaction and it didnt say it was so i assume that you had to assume it was a weak decay but similair to the 2015 omega particle the marking could be the same style.

    the rms voltage **** i got 229 V will i get follow on marks for using that?
    also i swear the power dissipapted or something is 4400W not 4040 because you are working out the power dissipated for a DC supply not the AC so thats why u dont convert it into the peak value? am i missing something

    as for the current in the last question i dont understand why its 5/18 and not 1/18, isnt the pd across the 18 ohm resistor 1V ? because you had 6V to start with and at the end u had 5V so 1V is lost in the resistor hence pd across resistor is 1V?
    but i did try using 1/18 and ended up getting a negative internal resistance which is obvioiusly wrong so i just went for the 5/18 and i miscalculated and got bloody 4.2ohms

    I agree with you here I don't understand why its 5v across the 18ohm resistor and not 1... anyone care to explain why its 5v not 1v!!

    also anyone know of an unofficial mark scheme anywhere?
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    (Original post by allofthestars)
    Im sure the resistance of the wires was in parallel not series ?
    It has to be in series as on wire goes from main to oven and the other oven to mains, to complete the circuit.
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    (Original post by txnilxnur)
    I agree with you here I don't understand why its 5v across the 18ohm resistor and not 1... anyone care to explain why its 5v not 1v!!

    also anyone know of an unofficial mark scheme anywhere?
    Because the total EMF was 6V, and the lost voltage due to internal resistance was 1V, so the current across the 18 ohm resistor was (6-1)/18 = 5/18 A
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    (Original post by thxmas7)
    It has to be in series as on wire goes from main to oven and the other oven to mains, to complete the circuit.
    For some reason i remember using p=RI^2 but i remember getting the same answer
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    (Original post by Ayaz789)
    Probs got around 46/70 will i get a B?
    Last year was 49/70 for an A so yeah sure
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    Anyone got an unofficial mark scheme for the paper yet?
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    (Original post by Improvement)
    Last year was 49/70 for an A so yeah sure
    Thanksa lot mate! Appteciate it that you replied! Ive got at least 80 ums yeah+
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    Hate coming on here to brag and stuff,
    but I do feel that exam went very well - which is a rare feeling when sitting an A Level Exam!

    Just a quick note to that cocky arse earlier calling everyone peasants while he will be getting full UMS - If you were so perfect you wouldn't be re-sitting titface.

    Best of luck everyone!
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    This exam was so piss, I genuinely thought it was a joke.

    Last year's exam I honestly found so hard, I thought they'd make this year's hard b/c they know everyone taking this is just re-sitting?
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    (Original post by mattismad)
    Hate coming on here to brag and stuff,
    but I do feel that exam went very well - which is a rare feeling when sitting an A Level Exam!

    Just a quick note to that cocky arse earlier calling everyone peasants while he will be getting full UMS - If you were so perfect you wouldn't be re-sitting titface.

    Best of luck everyone!
    I agree! This is rare for me too! Like last year I walked out PHYA1 in shock lol last year's paper was nuts
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    (Original post by shuu00)
    I agree! This is rare for me too! Like last year I walked out PHYA1 in shock lol last year's paper was nuts
    Ahahah tell me about it, completely same boat as you. No bloody potato question this year either. I skipped through the whole paper first just to make sure none of those *******s came up aha.
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    (Original post by Ayaz789)
    Thanksa lot mate! Appteciate it that you replied! Ive got at least 80 ums yeah+
    (Original post by Improvement)
    Last year was 49/70 for an A so yeah sure
    Last years paper was genuinely disgusting though. It's normally around 55-58 for an A but they had to drop it to 49 because of how many marks were dropped overall. I think it'll go back up to 55-58. There's no year 12s taking it and the paper wasn't that bad.


    smh. I still don't understand why aqa assumed we'd know the last question in the june 2015 paper was a parallel circuit. Or why I was tested on potato conduction.
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    (Original post by mattismad)
    Ahahah tell me about it, completely same boat as you. No bloody potato question this year either. I skipped through the whole paper first just to make sure none of those *******s came up aha.
    Last year left me traumatised hahaha like there were so many sneaky questions. This year the questions were pretty straight forward and I swear like 80% of them came up in past papers
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    (Original post by lucabrasi98)
    Last years paper was genuinely disgusting though. It's normally around 55-58 for an A but they had to drop it to 49 because of how many marks were dropped overall. I think it'll go back up to 55-58. There's no year 12s taking it and the paper wasn't that bad.


    smh. I still don't understand why aqa assumed we'd know the last question in the june 2015 paper was a parallel circuit. Or why I was tested on potato conduction.
    But 45 or 46/70 should get me above 80 ums though?
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    (Original post by MRuddyy)
    Personally I found that exam extremely easy and thrilling to read. I agree with most of the answers given in this post, however it must be said that some of the answers given here do not quite stand up to my par.
    I was aiming to achieve 80UMS, but after sitting it I expect myself to get- at least- 98UMS. Question 6+7 were rather quite easy, and a lot of the people on this post seem to completely blow the questions out of proportion.

    I'm praying to the Gods for you to all do well, however we all know that if you failed the exam then you yourself have no one to blame other than yourself- and no amount of attribution bias that is present will remove this fact.

    At the end of the day I will be achieving an A*, whereas most of you commoners will, maybe, scrap a C overall.
    See you all in the next post I grace you with my presence.
    Hahahahha you're an absolute mug, I'll eat my hat if you get an A*
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    (Original post by shuu00)
    Last year left me traumatised hahaha like there were so many sneaky questions. This year the questions were pretty straight forward and I swear like 80% of them came up in past papers
    Tbh i never liked the oscillator question! It was awful and i made so many silly mistakes ffs , i panic too much and im not the best in Physics , i really dont know why i picked it! I regret picking it, maybe i picked it because im good at maths which definitely doesnt help me!
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    (Original post by Ayaz789)
    But 45 or 46/70 should get me above 80 ums though?
    You might scrape 80 ums but I'm not sure. I thought this paper was easier than past papers and I reckon it'll be 56-58 for an A. Therefore you'll probably need 48-50 for 80 ums.
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    (Original post by TheLifelessRobot)
    You might scrape 80 ums but I'm not sure. I thought this paper was easier than past papers and I reckon it'll be 56-58 for an A. Therefore you'll probably need 48-50 for 80 ums.
    48-50 :O Ive probs got 75 ums then? Ill still be happy with that!
 
 
 
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