You are Here: Home >< Physics

# The Physics PHYA2 thread! 5th June 2013 Watch

• View Poll Results: What mark do you think you got out of 70?
0-20
6
3.00%
21-40
12
6.00%
41-50
29
14.50%
51-60
79
39.50%
61-70
74
37.00%

1. (Original post by lebron_23)
Just quickly, can anyone actually confirm what they got for the efficiency question? I seem to recall hearing various answers from people after the exam but not once did I hear what I was hoping for.

Also, if anyone is curious as to what the grade boundaries have been for the papers since June 2009, I'll be attaching a document that was rather nicely posted a bit eariler on this thread. Sorry creator of the Excel document, I hope I haven't violated any copyright laws!

Having them in a table just seems so much easier than using AQA's website to look for each year individually.. Ugh!
22.5%..ish..
2. (Original post by Aarongreatbanks)
I got this maybe take the good bits from mine if there are any and add to yours? Also what do you think I would get /70 I'd greatly appreciate it if someone gave me their scores

My mark scheme

1a) square root of 1000 squared+ 6000 squared
1b) 32
1c) 9.2
1d) 3900000
1e) 22%

2a)0.55
2b) 240
2c) the horizontal displacement =ut. It takes the same time to falls and u is less and therefore the distance travelled is less TOO VAGUE

3a)
Inital quick acceleration shown by steep gradient
As it falls a drag force is produced
As the object falls the drag force on it increases reducing the resultant force
F=ma with respect to Newton's second law and so the acceleration decreases as it falls as shown by the gradient getting smaller
Eventually drag is equal and opposite to weight
Ball travels at constant Velocity shown by the straight part of the graph near the end of time
Reference to Newton's first law as it moves at a constant velocity as there is no resultant force
Some of the energy of the object is converted into internal energy of the oil
It finally hits the bottom as shown by the vertical line at the end

3b) I did a striaght line to about 3/4 the way up the line before it hit the fluid
Copied the graph from the page before for the second bit but starter it lower to show it's speed falls when it hits the oil
Striaght line at the end

4a) I got the wrong as I said f *proportional sign* KL and defined the terms NO MARKS HERE
4b) 1200 n/m
4c) 9.4? I got this wrong I think I found how many squares there were and times by the area per square SHOULD HAVE BEEN 1.05
4d) the object is permanently stretched and doesn't return to its inital length
4e) striaght line to the x axis but a bit to the right than the first list as there is extension at the end of unloading

5a) n1>n2
Angle of incidence>critical angle

5b) 51
5c) 30
5d) it totally internally reflects as angle of incidence is more than critical angle DOES NOT REFLECT
5e) reflects away at same angle GOES AWAY FROM THE NORMAL

6a) 90 out of phase
270 out of phase

6b) up, down to equilibrium, down again, back up to equilibrium MENTION 1/4 OF A CYCLE... TOO VAGUE
6c) it's transverse as longitudinal can't be polarised THIS ONLY GETS 1 MARK
6d)1.7 x10 to the 8
6e) 750
6f) was there any more questions here?

7a) light consists of a single wavelength
7b) lower intensity, wider fringes
7c) don't shine it into people's face or look along the beam as it will damage the eye
7d) central white maximum, subsidiary maxima consisting of spectra with blue on inside and red on outside of the fringes. The intensity is less than laser light.

I think I got 54/70 maybe. As I've taken time to create this could you give me yor opinions on my score?
Didn't want to be too harsh so not correcting all your mistakes
3. Who found this paper harder than January 2013?
the grade boundary for an A was 50 for Jan 13, what do you reckon this ones will be?
4. (Original post by .raiden.)
Do you agree that the incidence angle is 30 degrees? 90-60? Thank you
I think that had to prove that the angle was 30 degrees for that question, so that would be correct.
5. (Original post by trentjoseph007)
JUST TO GET PEOPLES ATTENTION !!!

I think everyone misunderstood the last question on the paper. It was white light passing through a single slit. Look at the textbook page 202, figure 2. Apparently no one here realized it.

EDIT: It wasn't a easy question.
I think everyone realised? I haven't seen any respond to it as if it were a double slit question.

(Original post by Aarongreatbanks)
x
No obvious mistakes where I can see you've definitely dropped a mark (outside of the ones you've identified). A couple of words in there that they might penalise you for misuse or whatever. Most of the marks you'll drop will probably be if you haven't quite used the right terms or you've missed something silly. Hard to give an accurate estimate but I wouldn't think you'd be much lower than 52ish but I could be wrong. Physics and especially the written questions are ones where you can lose a fair few marks without realising it.
6. (Original post by ccashman)
Who found this paper harder than January 2013?
the grade boundary for an A was 50 for Jan 13, what do you reckon this ones will be?
recon about 47, because jan 13 was quite easy, and this was a bit harder, but not too bad
7. I am calling out AaronGreatBanks, I want to apologise for my misdemeanour towards your score, I hope you get the grade you want. Good luck
8. I found this exam quite hard but it's kind of worrying when everyone's saying it was easy

Posted from TSR Mobile
I think that had to prove that the angle was 30 degrees for that question, so that would be correct.
No this is the last part where we had to draw the path the ray, it reflected at 60 degrees and then refracted at a normal perpendicular to the previous normal. So the incidence was 90-60 = 30. 30< critical angle so refracts at 20.9 degrees to be specific (20.9 was not required).
10. (Original post by .raiden.)
No it is correct
I was being sarcastic to the guy saying there's definitely 8 per place.
11. (Original post by t-mister)
Didn't want to be too harsh so not correcting all your mistakes
I did mention a 1/4 of a cycle and even then I get around 13 lost so that's 57
12. (Original post by t-mister)
Didn't want to be too harsh so not correcting all your mistakes
I thought it did reflect for 5d?
13. (Original post by Aarongreatbanks)
I did mention a 1/4 of a cycle and even then I get around 13 lost so that's 57
I hope the grade boundaries are quite low this year as I do not think I got higher than 50. Are you planning on going to uni?
14. (Original post by HenryD)
I think everyone realised? I haven't seen any respond to it as if it were a double slit question.

No obvious mistakes where I can see you've definitely dropped a mark (outside of the ones you've identified). A couple of words in there that they might penalise you for misuse or whatever. Most of the marks you'll drop will probably be if you haven't quite used the right terms or you've missed something silly. Hard to give an accurate estimate but I wouldn't think you'd be much lower than 52ish but I could be wrong. Physics and especially the written questions are ones where you can lose a fair few marks without realising it.
15. (Original post by .raiden.)
No this is the last part where we had to draw the path the ray, it reflected at 60 degrees and then refracted at a normal perpendicular to the previous normal. So the incidence was 90-60 = 30. 30< critical angle so refracts at 20.9 degrees to be specific (20.9 was not required).
Don't think you had to write the angles on - it was only one mark.
16. (Original post by t-mister)
Didn't want to be too harsh so not correcting all your mistakes
It does totally internally reflect. You work out that the critical angle is 51 and you are giving the angle 30+22 as the approximate angle of incidence... hence TIR. For the question about the polarised waves. the deduction made can only be that the waves are transverse, this is because longitudinal waves cannot be polarised. Please if you do insist on marking others make sure that you know what the answers were.
17. [QUOTE=HenryD;42986565]I think everyone realised? I haven't seen any respond to it as if it were a double slit question.

OK so what would ur answer be?
18. Seems to be a lot of dissenting opinions on the optics question - did the ray refract or was it internally reflected?
19. (Original post by Goods)
It does totally internally reflect. You work out that the critical angle is 51 and you are giving the angle 30+22 as the approximate angle of incidence... hence TIR. For the question about the polarised waves. the deduction made can only be that the waves are transverse, this is because longitudinal waves cannot be polarised. Please if you do insist on marking others make sure that you know what the answers were.
That's what I thought ?
I thought it did reflect for 5d?
I may be wrong, but we won't know until the mark scheme comes out

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: September 15, 2013
Today on TSR

### Falling in love with him

But we haven't even met!

### Top study tips for over the Christmas holidays

Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• Poll
Useful resources

Can you help? Study help unanswered threadsStudy Help rules and posting guidelinesLaTex guide for writing equations on TSR

## Groups associated with this forum:

View associated groups
Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.