# General Thoughts: Physics (1 Viewer)

#### Rafy

##### Retired
Share your thoughts on the 2009 Physics exam here.

#### clonestar

##### Physicist/*******
2009 HSC Physics - How did you go?

People,

I will put in my multiple choice answers when I received a copy of the paper....hope it's a good paper find out shortly...

#### clonestar

##### Physicist/*******
Re: 2009 HSC Physics - How did you go?

Here is the MC section scanned:

2009 MC Physics.doc

I think a few may be wrong see what others say. Actually I am quite confident with them now feel free to rebut them..

1. C - sling shot changes direction and increases the speed of probe
2. A - mathematical ac=V^2/r
3. D - as the work done is the difference from infinity to geo and infinity to higher orbit. A is another correct possibility but not the best answer ???? Also why didn't they say infinity and instead say a very large distance away... arghhhh!!!

4. D - best answer as the range is different therefore X-Ux and Y-Ux are different but the objects hit the ground simultaneously as they have no vertical velocity.
5. B - gravitational force = G M1 M2/r^2 so therefore between sun and moon during lunar eclipse moon is at its furthest from the sun, hence r increases F decreases.
6. A - C and D are incorrect. Increasing rotational speed decreases the time therefore with Faraday's law EMF = -Change in flux/ time time decreases EMF increases.
7. C - rotates in the same direction as the magnetic field- being dragged along.
8. C - essential is induction which is the process of magnetic interaction between two coils
9. A - Use FBI rule to oppose the velocity direction with thumb(force) of left hand and index finger into the page then third finger points to the right which is conventional current + charge movement. Therefore + moves to the right and therefore electron must be on the left where p is. reverse thumb rule for electron direction..Nice question.
10. B - Confirmed....... This one will catch a few students... Agreed that Germanium is less abundant (some students would have chosen the converse for C which has Silicon as more abundant) and YES the energy level for Silicon is much more larger than germanium hence at higher temp it still remains a relatively good semiconductor... what a crazy question.... seems whoever wrote this gave there students an assignment on the history of germanium vs silicon. NSW BOS show em the outcome from the syllabus this question is based upon... GEEZ......
11. B - toque is a maximum at start and force is a maximum and constant as sin Theta is always 90 degrees on wire AB. Note the sync of the time scale for F and T and bingo dead give-away... OWND!!!
12. D - Absolutely definitely D with acceptor level just above valence band for p-type semiconductor
13. B - BCS theory of cooper electron pairs paring up i.e. joining together give away here is the word pairs fo electrons.. look for it
14. C - the work function for platinum is probably greater therefore more energy is required to eject it.
15. A - Electric field between two parallel plates is always constant. if they said electric field potential jesus what a question that would have been...LOL

I'll update more later
Actually the multiple choice is one fo the weirdest and trickiest for quite a while. Part B is not too bad the only interesting questions there are the Centripetal force mv^2/r applying it with magnetic force. qvbsintheta. I liked the transistor and replacement of thermionic valves...and Q27 you had a trick answer with none or no effect between intensity of light and KE only freq is proportional here.

Not a bad test certainly will differentiate in MC section more than anywhere else...
AS USUAL NO X-RAY CRYSTALLOGRAPHY for like now 6+ years there has never been a question on this area. LHC was speculated and did appear so well done to those users posting about it. Also what the heck was that question about the flexibility and strength of rubber bands..... boring.... World class paper... and your testing skills LOL... what a joke.. reading graphs might as well put a year 7 graph question in there BOS....LAME!!!!

I love Medical Physics awesome option... and great questions there too...

Enjoy

Last edited:

#### AnandDNA

##### Member
Re: 2009 HSC Physics - How did you go?

i got

1.C
2.A
3.C
4.D
5.C
6.A
7.C
8.C
9.A
10.B
11.D
12.D
13.B
14.C
15.A

#### biopia

##### WestSyd-UNSW3x/week
Re: 2009 HSC Physics - How did you go?

The physics exam was great
Minimum mark I calculated I could get was 89. That account for any question where I had any doubt at all. I am hoping to get above 92 though.
Overall, I though multiple choice was easy (only one or two that I really had to think about), the longer answers were OK. I thought they started hard and finished easy. The astrophysics questions were good too. Feel really confident with all of them. I even got onto a second writing booklet :S

I am so immensely happy that my HSC is OVER!

#### AnandDNA

##### Member
Re: 2009 HSC Physics - How did you go?

The physics exam was great
Minimum mark I calculated I could get was 89. That account for any question where I had any doubt at all. I am hoping to get above 92 though.
Overall, I though multiple choice was easy (only one or two that I really had to think about), the longer answers were OK. I thought they started hard and finished easy. The astrophysics questions were good too. Feel really confident with all of them. I even got onto a second writing booklet :S

I am so immensely happy that my HSC is OVER!

Hey can u post up your m/c questions im starting to get worried now

#### boxhunter91

##### Member
Q2Q was piss easy.
Stuffed up the light years and 60 degree bs..
Hopefully close to 80 if not more then 80 raw.

#### AnandDNA

##### Member
yeh pretty easy exam, Astro was really straight forward except for the 6 marker which i completely ignored in my study. Hopefully >85 raw

#### goby

##### New Member
WAY TOO MANY CALCULATIONS.

I thought the exam was only supposed to be 30% max. on calculations?

EDIT: Other than that, it wasn't too bad imo.

Last edited:

#### barnsy

##### Member
i must say, it was an easier exam than i thought it would be!!!
then again, in saying that, i'll probably fail!!!! haha
there were a few tough questions, but it wasn't too bad.

#### 08joel08

##### New Member
Re: 2009 HSC Physics - How did you go?

i got

1.C
2.A
3.C
4.D
5.C
6.A
7.C
8.C
9.A
10.B
11.D
12.D
13.B
14.C
15.A

i got the same on all except q's 9 and 13, i forget what they were on, i would acccept 13/15 : )

whatd everyone get on the messed up projectile motion question (Q 19 b) i got 5.9x10*-8

and for Q21 (c) i got 4.9x10*-6

can some1 confirm/deny?

lol it turns out i have the test right here, Q 9 im wrong because i did current not electrons, and Q 13 im pretty sure im right, because pair electrons dont experience attraction as a result of low temps but rather because of their interaction with crystalline structure, which behaves differently at low temps

Last edited:

#### Bdogz

##### Member
For that light year question, calculate the time taken did anyone get something lyk this : 2.396x10^10 seconds?

#### untouchablecuz

##### Active Member
Q2Q was piss easy.
Stuffed up the light years and 60 degree bs..
Hopefully close to 80 if not more then 80 raw.
nice question, it was a nicely snuck in projectile Q

#### AnandDNA

##### Member
Re: 2009 HSC Physics - How did you go?

yeh im pretty sure i got the same time for q.19.

i dont know what the question was for q.21

#### squeakyclean

##### New Member
yeah there was heaps of calculations
which i don't think were coming out for me gah
other than that it was ok

#### biopia

##### WestSyd-UNSW3x/week
Re: 2009 HSC Physics - How did you go?

Hey can u post up your m/c questions im starting to get worried now

Bear in mind, in my trial I lost more marks on MC than in any other section of the paper, but this is what I got.
C
A
C
D
C
A
C
C
C
B
D
D
B
C
A
The only difference in our answers is in question 9, which was one of the questions I was unsure about. I had minor doubts with 11 and 13 too. All I remembered about question 9 was that you use the right hand slap rule and face the palm in the opposite direction to the velocity given and this gives you the direction of the current. I forgot whether it was electron flow or conventional current :S. I hope that sufficiently explains my doubts hahaha.

Thanks for the good luck btw. To be honest, I don't think it will happen... Only two people in the history of my school have ranked that high... Oh well lol. A band 6 would be nice =]

Last edited:

#### Dx_God

##### Member
Re: 2009 HSC Physics - How did you go?

i'm around 95% sure tat q3 is c and d is just stupid(100% out) u might wanna correct it coz u obviously didn't get the real concept about GPE. and 5 is not b its a, b=100% out, a is around 95% correct (the earth in the middle attract sun and moon abit inwards due to gravitational attraction and hence reducing the distance between sun and moon and therefore INCREASING the force). and another 1...q11 is a) not b) (i'm around 99.99999999999% sure) because AB is always 90 degrees 2 the magnetic field no matter how it rotates while from the equation t=nBIAcosq its obviously a cos curve...). don't know where did u get those answers from but i'm sure these r wrong (i can call bos 2 argue seriously if tat was the correct answers).

Last edited:

#### AnandDNA

##### Member
For that light year question, calculate the time taken did anyone get something lyk this : 2.396x10^10 seconds?
i got like 790ish years. i think 796 im not sure

edit: just used my calculator and yeh my answer in years is near your answers in seconds

Last edited:

#### Bdogz

##### Member
i got like 790ish years. i think 796 im not sure
Yeah thats wat my answer is in seconds