CSSA trial: physics thoughts (1 Viewer)

Futuremedstudent

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Hi class of 2014,
please post your thoughts on the CSSA physics paper.
Best of luck and all the best in your studies.
 

photastic

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Multiple choice was pretty challenging, prob the hardest part, the rest was straightforward from the syllabus
 

90atarpls

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i fucked up projectile motion, i used the wrong formula and got the velocity in terms of T GGGGGGGG
FUCK ME
GG 6 marksssss
 

the_lebtalian

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Was pretty decent, although the 7 marker threw me off, I didn't write as much as I could've for it
 

90atarpls

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was the last astrophys question abt emission/cont/absporbtion spec?
 

TrentsUnicorn

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Multiple choice was pretty challenging, prob the hardest part, the rest was straightforward from the syllabus
Yeah mc messed me up, I had to guess a couple and I forgot the shit about Einstein/Planck so I screwed that too
 

panakap

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was the last astrophys question abt emission/cont/absporbtion spec?
It was about how we use spectroscopy to determine the motion of objects... both rotational and translational velocity.

But my question is for astro,
1. Why was it such a difficult section
2. What in the world is the experiment for the colour filters (B-V) stuff
 
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panakap

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Was pretty decent, although the 7 marker threw me off, I didn't write as much as I could've for it
I wrote surprisingly a lot EXCEPT for the the fact that all I could write for a successful orbit is that the orbit can't be too low or else it will crash back down to Earth. It needs to be traveling at the right speed according to the idea of escape velocity
 
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panakap

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Multiple choice was pretty challenging, prob the hardest part, the rest was straightforward from the syllabus
I think I must be lucky my teacher didn't like how the MC was written so she made her own one up... which worked in my favour because 16/20 were just math questions and 4 were simple physics ideas haha I had no special relativity in my paper at all. I think she changed it coz there was heaps of ITI in it or something, we only got tested for 25 marks on Focus 1

[e] There was so much math in this paper I loved it <3
Projectile wasn't an easy one to get around but a very nice question CSSA
 
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photastic

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I think I must be lucky my teacher didn't like how the MC was written so she made her own one up... which worked in my favour because 16/20 were just math questions and 4 were simple physics ideas haha I had no special relativity in my paper at all. I think she changed it coz there was heaps of ITI in it or something, we only got tested for 25 marks on Focus 1

[e] There was so much math in this paper I loved it <3
Projectile wasn't an easy one to get around but a very nice question CSSA
WTH! Lucky you, there was hardly any maths, only like 10 marks worth of calculations. Lol, teacher crossed out question 19 because he thought the question was ambiguous. Your teacher must really love you guys, one mc took me 15 minutes to calculate. But then, the projectile motion was a bit disappointing but the left hand side of the diagram was probably there to troll people because it could've easily been cropped out, still waiting for a rebound case.
 
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panakap

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WTH! Lucky you, there was hardly any maths, only like 10 marks worth of calculations. Lol, teacher crossed out question 19 because he thought the question was ambiguous. Your teacher must really love you guys, one mc took me 15 minutes to calculate. But then, the projectile motion was a bit disappointing but the left hand side of the diagram was probably there to troll people because it could've easily been cropped out, still waiting for a rebound case.
Even the amendments my teacher made (all from ITI focus 1) were simple stuff; Thomson's experiment, field between two charges, the force on a particle and the debate about what cathode rays were... I really must be lucky because this might be just me but the rest of ITI in that paper looked difficult, and I wouldnt have been prepared for the comparison of Planck/Einstein and Edison/Westinghouse haha

Yes true the projectile diagram was a little confusing.. I even at first used the vertical displacement as 12m before I realised the skier jumped at the END of the ramp, therefore it was 16m :/
 

photastic

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Even the amendments my teacher made (all from ITI focus 1) were simple stuff; Thomson's experiment, field between two charges, the force on a particle and the debate about what cathode rays were... I really must be lucky because this might be just me but the rest of ITI in that paper looked difficult, and I wouldnt have been prepared for the comparison of Planck/Einstein and Edison/Westinghouse haha

Yes true the projectile diagram was a little confusing.. I even at first used the vertical displacement as 12m before I realised the skier jumped at the END of the ramp, therefore it was 16m :/
But then again, after learning projectile motion in extension 1 math, it makes every physics projectile so easy. Nah, ITI wasn't that hard tbh, nor there wasn't a long response for relativity (surprised)
 

panakap

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But then again, after learning projectile motion in extension 1 math, it makes every physics projectile so easy.
Yes very true haha it was pretty easy coz in Ext1 there is so much more they can ask... and it's not put into parts for you


Nah, ITI wasn't that hard tbh, nor there wasn't a long response for relativity (surprised)
Me too I'm surprised no relativity but rather a 7 marker on a successful rocket launch haha.

Also the only Lenz's Law occurred with the toy car and the aluminium plate, pretty easy actually it's gonna slow the velocity down slightly, acting like friction. Also what value did you get for the altitude of the geostationary orbit? From memory mine was around 42000 km I think
 

photastic

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Yes very true haha it was pretty easy coz in Ext1 there is so much more they can ask... and it's not put into parts for you

Me too I'm surprised no relativity but rather a 7 marker on a successful rocket launch haha.

Also the only Lenz's Law occurred with the toy car and the aluminium plate, pretty easy actually it's gonna slow the velocity down slightly, acting like friction. Also what value did you get for the altitude of the geostationary orbit? From memory mine was around 42000 km I think
It's 36000km, you use Kepler's equation to find r, then you minus r and 6380km.
Also I bet most people forgot about the aluminium plate and probs only wrote that it accelerates down due to gravity.
 

panakap

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It's 36000km, you use Kepler's equation to find r, then you minus r and 6380km.
Also I bet most people forgot about the aluminium plate and probs only wrote that it accelerates down due to gravity.
Yes I did that but I got 48000km before I minused the 6384km... :/ hmm I wonder because I thought it was approx 35000km but my maths told me otherwise
 

photastic

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Yes I did that but I got 48000km before I minused the 6384km... :/ hmm I wonder because I thought it was approx 35000km but my maths told me otherwise
r^3/T^2 = GM/4pie^2
r = cuberoot(GMT^2/4pie^2)
r = cuberoot[(6.67x10^-11)(6x10^24)(86400^2)/4pie^2)] = 42298km
therefore altitude = 42298-6371 = 35927km
 
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panakap

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r^3/T^2 = GM/4pie^2
r = cuberoot(GMT^2/4pie^2)
r = cuberoot[(6.67x10^-11)(6x10^24)(86400^2)/4pie^2)] = 42298km
therefore altitude = 42298-6371 = 35927km
Wait maybe I was fine I got 42298 before I minused it I must be dillusional lmfao sorry yeh I got it :p
 

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