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anomalousdecay

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Force component is just weight * sin theta, try putting theta from 1 degree to 89 degree and you will understand how it works

my attempt to the block on slope question was F - mgsin theta - umgcos theta = ma
but I cant explain the deduce a theta for largest F.
Well that one degree to 89 degree makes sense.

But I still don't know how to derive it using triangles.

I put something similar.

I think I had sum of forces = ma = mgsin theta + umgcos theta

And I put y component of force is zero overall but I think that had nothing to do with the question, but nevertheless I had N - mgcos theta = 0.

But yeah probably got it wrong.

So glad though that q1 was so simple and easy. Fixed up my mechanic section with that despite probably getting around 15-20/40 for the rest of mechanics section.
 

anomalousdecay

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For that maximum force question, I think you can differentiate with respect to theta then get the maximum from there.
Yeah that's what you are supposed to do.

But I had nothing from the first part to begin with lol.
 
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4025808

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I did it all but I have a feeling that a majority of calorimeter part was wrong.

Like the final temperature I got something in the 20's degrees celsius which I think is wrong, but then again I have the carry on error so not sure :/

PV diagram was easy though, should get 15/15 there. inb4 mistake.

damn hoping for pass. Why couldn't we just go back to pre 2011 so that you pass without passing the final.
I'm guessing its coz they probably realized that a lot of people were cheating on the quizzes so they made such a requirement to fail the ones who cheated on quizzes and never properly learned the content.
 

4025808

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For that maximum force question, I think you can differentiate with respect to theta then get the maximum from there.
Yeah that's what you are supposed to do.

But I had nothing from the first part to begin with lol.
Oh thank god I actually got that. Nothing else to differentiate with so yeah. Thank goodness I was on the right track haha.
 

anomalousdecay

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Oh thank god I actually got that. Nothing else to differentiate with so yeah. Thank goodness I was on the right track haha.
It kinda sucks that I couldn't get the first part so that I could do the differentiation so I lost the marks.
 

4025808

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Though tbh you could sorta guess that question if you still remembered mechanics from 4U maths. Also if you did the 2013 S2 paper you would have noticed that the question was a tad similar to that of the 2014 S1 one.

Think my raw mark might now be around the 60s. hmm

Oh well. ENGG1811 come at me (more like ENGG1811 will come at me :( ).
 

anomalousdecay

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I didn't do that bad lol.

I do think I passed. Its just that there might be the chance I had an error in something which goes unmasked and gg supplementary exam time.

And after doing all 9 new syllabus past papers, I found this paper more difficult than any of them because I could not do a fair bit of the mechanics questions in it and I got a bit of thermal wrong. Otherwise if I did not stuff up a few thermal marks and actually understood resolving force components then I would have done well (I never have to touch mechanics again in my whole program fk they should have just let us accelerate into phys 1b without doing 1a ffs).
 

anomalousdecay

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Though tbh you could sorta guess that question if you still remembered mechanics from 4U maths. Also if you did the 2013 S2 paper you would have noticed that the question was a tad similar to that of the 2014 S1 one.

Think my raw mark might now be around the 60s. hmm

Oh well. ENGG1811 come at me (more like ENGG1811 will come at me :( ).
Yeah long story short I got 89 in MX2 without doing that section of mechanics ever lol.

Same my raw might hit that area but for higher phys that's min lol :/

On the bright side I either fail or get a credit lol.
 

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Though tbh when I saw the paper, I felt that it was pretty unexpected (esp the Justin Bieber bit wow) of them to test the stuff they tested us today. Especially the calorimeter bit and the first + last questions.
 

anomalousdecay

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Though tbh when I saw the paper, I felt that it was pretty unexpected (esp the Justin Bieber bit wow) of them to test the stuff they tested us today. Especially the calorimeter bit and the first + last questions.
Last question was good because it mixed quite a lot of different concepts in there such as doppler effect, SHM, resonance, etc, so it was a good question.

However the spring question had wording which made me ponder for too long and waste time (I got this feel from 5)c) too). Idk, but I could not figure out whether they stayed together or not after the collision even though at max compression relatively v = 0 to each other and that I could get out the energy of the system correct hopefully to find x (I honestly did that question once, then crossed out the whole thing and did it again because it took ages to realise what was going on).

I still can't remember what q3 part b was (someone trigger my memory please lol).
 

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