Advanced Higher Mechanics

Anyone got some rough solutions for this year's 2016 AH Mechanics. Here's a link to the paper:
https://drive.google.com/file/d/0B3YEN8QuM_lxanlDQ0RabmV1VG8/view?usp=sharing

Anyone got some rough solutions for this year's 2016 AH Mechanics. Here's a link to the paper:
https://drive.google.com/file/d/0B3YEN8QuM_lxanlDQ0RabmV1VG8/view?usp=sharing

Hi! Might be good to start a new thread about this in the SQA forum - this thread that you're posting in now is two years old

Thought it was quite a mixed paper. Some really simple questions but other parts were really tricky. I agree it was more difficult than the past or specimen papers.
Qs 1-8 were okay
Q9 I got an answer but not confident. Definitely lost marks for stating assumption.
Q10 I thought was okay
Q11 I'm glad I looked over using integration to find center of mass for a curve lamina the night before - that would really have caught me out otherwise.
Q12 I chose a really convoluted process (should've just used cosine rule) for vectors but hopefully I still got the marks for a right answer. Probably didn't explain about return journey properly.
Q13 I'm not confident about volume
Q14 Really convoluted method but eventually rearranged and got the expression.
Q15 I didn't show that the acceleration was equal to 0 in part c) which makes me think I solved the differential equation wrong in part b)
Q16 and 17 I'm happy with

But I'm not worrying too much. Look at the grade boundaries for last year:

Yeah I agree that Qs 1-8 were okay, although pretty sure I answered Q3 wrong as I just took the magnitude of the force vector and multiplied it by the magnitude of the relative displacement vector My teacher thought this was okay but now I'm pretty sure you have to do the dot product. Also for Q6 I think they could have been more clear about what was point A and what was point B. It said in the question that the aircraft "is flown from point A from point B" which implies that the distance AB doesn't include the time it was on the ground before take-off but I didn't really think the SQA meant this so I just assumed it did include this time.

Q9 I was quite happy to see come up cause I'd just revised it the night before but I'm pretty sure I got it wrong... How many laps did you get? I got 5 but when I did it at home after the exam I think I got 4. Probably made a stupid arithmetic error somewhere. I said for the assumption that we assume the cyclist is travelling in exact circular motion but doubt that's right.

Ughhh Q11 I had no clue how to do Don't think we even went over that in class so I just had to leave it out.

I got really confused at Q12 because I started off just assuming the wind was coming from the south and then realised that was really stupid. I moved on to the next question cause it was taking too long. Intended to go back and answer it but I completely ran out of time (that's 8 marks down the drain).

Q13 I thought was fine at first but when I tried part b, I got x = 32, which is obviously wrong and then I realised the volume I calculated in part a must have been wrong as well Didn't have time to fix it though so that was very annoying.

Ughh I was quite happy to see Q14 come up as it's my favourite type of question but I just could not get to the final expression. I actually had the right method and got really close to the end but didn't manipulate it any more cause I thought there was no way I was right.

Q15 was fine for me I think and I managed to get acceleration equal to zero.

Q16 was okay at first and I thought I knew what I was doing for part b but I obviously made a really stupid error somewhere cause I was left with 20tantheta=9h whereas when I did it again at home I got 20htantheta=9h which cancels down... It's so infuriating that I could do practically all the questions after the exam but during it I kinda panicked

And yeah Q17 was fine I think. Did you get u>root5rg for question a(ii)?

I got 94% in the prelim but I doubt I've even got a B for the exam Actually if the grade boundaries are similar to last year like you pointed out then I might get an A but I feel like they won't be that low. Have you asked anyone else how they found the exam? Everyone in my class said it was really hard as well so I guess there is still a good chance the boundaries will be low. Sorry for the long post btw it's just good to find someone else that did AH Mechanics

Yeah - pretty sure you need to do dot product for 3.
I agree 6 was a bit ambiguous. I also assumed the take-off time was included.
For 9 I got the cyclist's speed to be around 18ms^-1 which led about to 29 laps? I've probably gone wrong somewhere as I don't think track cyclists go that fast.
For question 11 I think you integrate y^2 with respect to x between 0-4 and divide by the area of the curve to find x coordinate and integrate 0.5xy with respect to x between 0-4 and divide by the area of the curve to get y coordinate. Its new to the course this year.
For 12 I think I drew out the vectors correctly but overlooked the fact that I could apply cosine rule and instead subdivided into smaller right angled triangles and used SOHCAHTOA and pythagoras to find magnitude and direction.
Q13 I got a volume of about 2500 and if I remember right I got about 11 for part B.Q15 I tried again now. Turns out I did the differential equation right (I worked backwards and checked). I guess I just made an error with part c)
Q16 I've just realised I made an error. Didn't notice it said h metres further. Hopefully only lose 2 marks with follow-on for subbing in h instead of 5h.
Q17 Got u > sqrt(5g) same as you.

I'm the only one doing it at my school so I've had no-one to talk to about it. Im glad to find it wasn't just me that found it hard. Hopefully the grade boundaries are as crazy as last year - going through it I dont think I've got worse than 70% which could potentially be band-1.