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AQA Physics PHYA4 - 20th June 2016 [Exam Discussion Thread]

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So do we indeed get an answer sheet for section A or just circle on the paper?


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We don't have to include working out on the multiple choice sheets, do we? I usually just do rough work on a blank piece of paper.
Original post by rory58824
We don't have to include working out on the multiple choice sheets, do we? I usually just do rough work on a blank piece of paper.


Only the final answers (which you enter onto a separate answer sheet) are marked.
For q15 on the jun15 paper, can someone explain why it's upwards?
http://filestore.aqa.org.uk/subjects/AQA-PHYA41-QP-JUN15.PDF
Original post by Seclusion
For q15 on the jun15 paper, can someone explain why it's upwards?
http://filestore.aqa.org.uk/subjects/AQA-PHYA41-QP-JUN15.PDF


In an electric field the force experienced by a positive charge is in the same direction as the field points.

Weight acts downwards so the force must act upwards to balance it and so the field must also point upwards.
Original post by Seclusion
For q15 on the jun15 paper, can someone explain why it's upwards?
http://filestore.aqa.org.uk/subjects/AQA-PHYA41-QP-JUN15.PDF


A positive ion will have weight going down and so if it is in equilibrium the electric force on it must be acting upwards.

The direction of the electric force is the direction a positive particle would go and thus it is upwards


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Am I the only one who really likes the multiple choice section...
Original post by Messier31
Am I the only one who really likes the multiple choice section...


Nah I love them too - I'm hoping for 25 in it tomorrow :tongue:


Posted from TSR Mobile
Jan 13 all of question 1... What on earth are AQA doing? Why can't they agree with the rules that THEY implemented? Significant figures in the mark schemes they're using are a joke. I don't care if you're only tested on them once per paper, it's still ridiculous to see them use 2 sig figs throughout the question, then as an answer, round 2.6666 to 2.6. I'm sorry but that's wrong.

Then on 1biii they use incorrect rounding from values given ON THE FORMULA SHEET. They change 1.67*10^27 to 1.66*10^27 for no reason. Why're they even rounding with forumula sheet values? More importantly, why are they rounding incorrectly? Because the more accurate proton mass would be 1.673*10^27, which rounds down to 1.67*10^27.

And then there's the issue of using answers from previous questions to answer the next one. Am I supposed to use the answer I put in the answer box? Or the exact answer I got on my calculator? If this were a non retarded exam board I could just go look through past papers and check. But oh wait, they change which one they do every mark scheme.
Original post by kingaaran
Nah I love them too - I'm hoping for 25 in it tomorrow :tongue:


Posted from TSR Mobile


Same :smile:

If you get 25 you have a huge margin for error in section B
Original post by lucabrasi98
Jan 13 all of question 1... What on earth are AQA doing? Why can't they agree with the rules that THEY implemented? Significant figures in the mark schemes they're using are a joke. I don't care if you're only tested on them once per paper, it's still ridiculous to see them use 2 sig figs throughout the question, then as an answer, round 2.6666 to 2.6. I'm sorry but that's wrong.

Then on 1biii they use incorrect rounding from values given ON THE FORMULA SHEET. They change 1.67*10^27 to 1.66*10^27 for no reason. Why're they even rounding with forumula sheet values? More importantly, why are they rounding incorrectly? Because the more accurate proton mass would be 1.673*10^27, which rounds down to 1.67*10^27.

And then there's the issue of using answers from previous questions to answer the next one. Am I supposed to use the answer I put in the answer box? Or the exact answer I got on my calculator? If this were a non retarded exam board I could just go look through past papers and check. But oh wait, they change which one they do every mark scheme.


Rant over? Save it for tomorrrow, they might give us an unusual paper.
Original post by rory58824
Rant over? Save it for tomorrrow, they might give us an unusual paper.


Smh if they aren't even competent enough to make a mark scheme with no errors then I wouldn't be surprised if they accidentally put in a question with no valid solution in for the test tomorrow (as they do once every few years).
Original post by lucabrasi98
Smh if they aren't even competent enough to make a mark scheme with no errors then I wouldn't be surprised if they accidentally put in a question with no valid solution in for the test tomorrow (as they do once every few years).


Wouldn't surprise me, but if you're unsure on a question, try and write something down at least, they seem quite keen on working marks, or even quoting a formula.
Original post by lucabrasi98
Jan 13 all of question 1... What on earth are AQA doing? Why can't they agree with the rules that THEY implemented? Significant figures in the mark schemes they're using are a joke. I don't care if you're only tested on them once per paper, it's still ridiculous to see them use 2 sig figs throughout the question, then as an answer, round 2.6666 to 2.6. I'm sorry but that's wrong.

Then on 1biii they use incorrect rounding from values given ON THE FORMULA SHEET. They change 1.67*10^27 to 1.66*10^27 for no reason. Why're they even rounding with forumula sheet values? More importantly, why are they rounding incorrectly? Because the more accurate proton mass would be 1.673*10^27, which rounds down to 1.67*10^27.

And then there's the issue of using answers from previous questions to answer the next one. Am I supposed to use the answer I put in the answer box? Or the exact answer I got on my calculator? If this were a non retarded exam board I could just go look through past papers and check. But oh wait, they change which one they do every mark scheme.


Why is it wrong - you will get the marks if you write 2.7, the brackets are to show examiners what the other significant figure needs to be to ensure candidates have used a valid method.

In response to your second question, they've used the atomic mass unit, not the mass of the proton which is of course correct - on their formula booklet they clearly say u=1.661 x10^(-27)


Posted from TSR Mobile
Anyone know if we need to use the right hand rule for generators? Haven't seen it at all in past papers.
Okay going to watch a few videos to reinforce my knowledge then do mc sections......

Just doing capacitance and wanted to check my knowledge

Is the reason the current reverses during discharge because before the path to the only positively charged section (the cell) goes through the capacitor, and after you cant reach that section as the switch has blocked it, so now the only positively charged area is the rear of the capacitor which is now accessible?

Also is the reason the of across a capacitor never actually equals the pad across the cell because it is exponential, and so will only equal the cells pd when time=infinite seconds?
Prediction on this years 6 marker?
Original post by rory58824
Anyone know if we need to use the right hand rule for generators? Haven't seen it at all in past papers.


The one with the thumb being the current and the fingers being the field direction?


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Original post by kingaaran
Why is it wrong - you will get the marks if you write 2.7, the brackets are to show examiners what the other significant figure needs to be to ensure candidates have used a valid method.

In response to your second question, they've used the atomic mass unit, not the mass of the proton which is of course correct - on their formula booklet they clearly say u=1.661 x10^(-27)


Posted from TSR Mobile


1. It's not about what you get the marks for. I still got the question right, I just hate seeing them write 2.6 as and an answer when you the accurate solution is 2.666. That was obviously an accident by them. They pull stuff like that every year.

2. Honestly I didn't notice the atomic mass unit. But I still fail to see why they're using that when an alpha particle is just 2 protons and 2 neutrons. What would I do in an exam then? And what's the point of specifying proton and neutron masses if sometimes they just use atomic mass instead?

3. The whole issue with whether to use rounded answers for the next question or accurate answers still gets on my nerves. I wouldn't mind if they just settled on one way but they genuinely change their minds as they see fit. Which is a problem as sometimes using the one they don't want gets you "incorrect" rounding. E.g them wanting 2700 but you getting 2763 and rounding to 2800 because you either used the accurate or rounded answer from the last question and they wanted you to use the opposite
Original post by kingaaran
Why is it wrong - you will get the marks if you write 2.7, the brackets are to show examiners what the other significant figure needs to be to ensure candidates have used a valid method.

In response to your second question, they've used the atomic mass unit, not the mass of the proton which is of course correct - on their formula booklet they clearly say u=1.661 x10^(-27)


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Do we have to use the atomic mass unit then?


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