2009 Physics Unit 3 Exam Suggested Solutions

[UprightMan]

AHH *&!@.  I knew I got that loop de loop question wrong...but according to your suggested solutions Mao, I've done pretty well...Thanks heaps Mao!  Damn loop de loops...

[kurrymuncher]

Im not sure about half marks, but your bound to get 1 or 2 marks for the apparent weight question, if you showed working

[Mao]

I'm concerned. So many people claiming high scores...is that just because of the intellect of the people on this forum is wayyyy above average, or did the rest of VIC find it easy too?

You'll find that the people who have enough motivation to come to a VCE discussion site, actively participate in community discussion, help each other out and do things of that like, tend to be the better students of the state

[TrueTears]

for the apparent weight question. i wrote 720. how many marks would i lose?
and also in the modulation question, i got 1 right.
is that a half mark?

I *think* you might lose 2 marks for the 720 question. Because 2 marks are for methods and 1 is for answer, the answer mark is consequential (meaning if your method is right but subbed in a wrong value, then even though your answer is wrong it still gets a mark, unlike other subjects like methods.) But if you get 720, it would mean your method had a problem as well.

[dejan91]

I'm concerned. So many people claiming high scores...is that just because of the intellect of the people on this forum is wayyyy above average, or did the rest of VIC find it easy too?

You'll find that the people who have enough motivation to come to a VCE discussion site, actively participate in community discussion, help each other out and do things of that like, tend to be the better students of the state

Hmm I thought so. Anyway, thanks for the worked solutions Mao

[TonyHem]

For that question, I got 720 ( wrong), would I get a mark for doing:

Taking up as positive
Fnet = Fn+fg
Fn = 2 x 60 = 120
FG = 60 x -10 = -600
120 = Fn -600
Fn = 720

Based on those solutions, got the "h"value wrong and this q. :[

[UprightMan]

Did anyone get 100%?

[TrueTears]

For that question, I got 720 ( wrong), would I get a mark for doing:

Taking up as positive
Fnet = Fn+fg
Fn = 2 x 60 = 120
FG = 60 x -10 = -600
120 = Fn -600
Fn = 720

Based on those solutions, got the "h"value wrong and this q. :[

I think you'd get 1/3 for that question.

You would have lost 1 for method, 1 for answer (since your answer was not consequential due to wrong method ; should have been )

[Mao]

For the selected few who decided to do Special Relativity, the solutions are now up on first post.

Congratulations to all students, you have all survived Unit 3. [Rumour has it that unit 4 is easier]

I have referenced my solutions to Itute, everything is in agreement except where I didn't read the question properly. That has been corrected in Errata also in first post.

I will be happy to answer specific questions anyone may have. And I appreciate all those 'thank-you's being thrown around

Once again, congrats, and those of you who have chem tomorrow, toodles, go study

[avram_grant]

what do you guys reckon the average was? i reckon about high 60s, low 70s - generally the state makes silly errors

[Mao]

For that question, I got 720 ( wrong), would I get a mark for doing:

Taking up as positive
Fnet = Fn+fg
Fn = 2 x 60 = 120
FG = 60 x -10 = -600
120 = Fn -600
Fn = 720

Based on those solutions, got the "h"value wrong and this q. :[

I think you'd get 1/3 for that question.

You would have lost 1 for method, 1 for answer (since your answer was not consequential due to wrong method ; should have been )

I believe he should get 2/3. The only mistake he made was he mistook a=-2 for a=2. Everything else were consequential.

[nbalakers24]

how long did it take you to wirte up the solutions Mao?

[dejan91]

what do you guys reckon the average was? i reckon about high 60s, low 70s - generally the state makes silly errors

Well considering it was around last years difficulty (and the average was 64% last year), around 60-70% would be about right.

[Mao]

what do you guys reckon the average was? i reckon about high 60s, low 70s - generally the state makes silly errors

Overall, it wasn't a hard exam. The questions were fairly simple, but it was long. The state average should remain what it has in previous years, A+ cut off would be 10~14 marks.

[Mao]

how long did it take you to wirte up the solutions Mao?

With interruptions, ~1.5hrs