** LC Applied Maths 2014 - Before and after discussion **

qweerty

A thread for the supreme subject that is App Maths.

This is the ranking of the questions in terms of popularity in 2012:

1. Linear Motion
2. Dynamics
3. Collisions
4. Projectiles
5. Differential Equations
6. Relative Velocity
7. Rigid-body Motion
8. Circular Motion/SHM
9. Statics
10. Hydorstatics


The first four were answered by over 90% of candidates. With the exception of Hydrostatics, each question's popularity-rank was within two places of its performance-rank.

In the four years for which information is available since 2000 (Chief Examiner's Reports), in only one year has one of the trio of CM/SHM, Statics and Hydrostatics had more than a 20% response-rate.

In Q1, the trend has been to alternate part-b between a more involved equations-of-motion question than part-a (usually a horizontal acceleration question involving two particles or one particle with information about different stages of its motion) and a Velocity-Time graph question. Last year's part-b was a V-T graph.

Q4 hasn't had a wedge part-b in ages.

The Physics Teacher is a very good resource which has notes and an incomplete archive of past papers going back to the 70s. I would advise that, at this stage, no one try to study his notes, as the way in which different teachers approach questions can differ quite a lot.

What you need for the exam:

Writing implement
Calculator
Log tables
Ruler and pencil
Lucky teddy bear

Huell

A paper like the mock and ill be set

Raspberry Fileds

Great OP!

In the context of the format of the App Maths paper having remained strikingly unchanged for over a decade, I think the several minor oddities* on last year's paper should be seen as an explicit indication by whoever sets the paper that they intend to start being more adventurous. What's also interesting is that all the other questions were entirely usual. Therefore, I think we'll see one of 1, 3, 4, having a slight twist or unusual format.


*5(b), 6(a), 10(c)

TheBegotten

I'm surprised at the hydrostatics rate, that's normally (I think) quiet tame compared to the rest of the questions.

For myself it depends on Q1 and Q4. If they're nice we'll all be laughing...

How are people fixed for calculus? I know a lot of people don't do it after the changes in the maths course.

CelestialKing

Didn't a wedge come up last year? They are soooooo easy! I would kill for one!!

You should definitely be doing Q10 now with the changes, no more substitution (not that it's hard, just takes longer). The question is severly nerfed and you'll be saving tonnes of time by doing it. Other Qs take about 23 mins whereas Q10 takes 10-15 mins so I recommend that.

As for me I'll be banking on:

-1 Projectiles
-2 Connected Particles
-3 Differential Equations
-4 Collisions
-5 Linear Acceleration
-6 Relative Velocity

For no reason at all, relative velocity is my worst answered, any general tips? I may scrap it for Simple Harmonic because Circular Motion is the easiest thing on the course!

What're you guys hoping for, result-wise?

Huell

I would love an A1 or A2 but it purely depends on how the paper is urself?

qweerty

Those stats can be misleading: there's no knowing the calibre of students who would attempt minority questions.

Don't remember, but it's been four or five years since a wedge. They can get pretty involved, especially if there ar emultiple paticles, two faces, friction with the ground, etc.

1-5 and 10?! No originality! I think RBM may be the easiest question on the course.

CelestialKing

qweerty wrote: »

Those stats can be misleading: there's no knowing the calibre of students who would attempt minority questions.

Don't remember, but it's been four or five years since a wedge. They can get pretty involved, especially if there ar emultiple paticles, two faces, friction with the ground, etc.

1-5 and 10?! No originality! I think RBM may be the easiest question on the course.

Last I checked it wasn't an originality test! If it was I'd be doing Hydrostatics. Has it really been that long for a wedge? I want one sooo badly! We didn't study RMB so I wouldn't know how easy it is, which Q is it normally on the paper?

I really need an A1. Don't know if I can pull it off. 2 days free before the exam though

PaleMoonlight

I've 7 questions covered, should I aim to get 7 done or just 6 and leave out the one I think is hardest?

CianDowd

My plan is to do:
1, 2, 3, 4, 5, 10.
I may do 6 instead of one but I'm out of practice on them.

I really want Q4 to avoid wedges but I think that they're due up.

We had a teacher swap at Christmas and I did poorly in the mocks as a result of that and other things but I'm hopeful that I'll do much better in the real thing.

Anyone else hoping that wedges won't come up?

CelestialKing wrote: »

Has it really been that long for a wedge? I want one sooo badly! We didn't study RMB so I wouldn't know how easy it is, which Q is it normally on the paper?

It has been that long since wedges came up. I don't want one but the odds are in your favour.

I tried RBM but as I'm not good at rote learning so the proof parts were tricky for me and I struggled with the second part too.

PaleMoonlight wrote: »

I've 7 questions covered, should I aim to get 7 done or just 6 and leave out the one I think is hardest?

If you stick to about 20 mins a question then you should have time for a seventh but it can be hard to stick to that and I generally find it's more useful to go back to others if I have time.
Still if you're confident with what you've done and you have time you could try a seventh if you were up to it.

PaleMoonlight

CianDowd wrote: »

If you stick to about 20 mins a question then you should have time for a seventh but it can be hard to stick to that and I generally find it's more useful to go back to others if I have time.
Still if you're confident with what you've done and you have time you could try a seventh if you were up to it.

Thank you, I'll try do the 7 then I managed it in the last mock I did so hopefully I'll do it again

mcratsix

PaleMoonlight wrote: »

I've 7 questions covered, should I aim to get 7 done or just 6 and leave out the one I think is hardest?

If I were you I wouldn't plan on doing seven. Pick your best six and do them carefully and slowly, try to get as many marks as you can even if you get stuck on a question. Sometimes you'll get a question done quickly, like q10 can be really simple, so if you've 20 mins to spare then sure, do another q. But i wouldn't put myself under pressure to do 6 questions quickly so I can cram in a 7th, you'll just make mistakes.

CianDowd wrote: »

My plan is to do:
1, 2, 3, 4, 5, 10.
I may do 6 instead of one but I'm out of practice on them.

I really want Q4 to avoid wedges but I think that they're due up.

We had a teacher swap at Christmas and I did poorly in the mocks as a result of that and other things but I'm hopeful that I'll do much better in the real thing.

Anyone else hoping that wedges won't come up?

I basically have the exact same plan for the exam, hoping wedges don't come up either, but i think if they do I could do it. Q8 and q1 are interchangeable for me, sometimes q1 can actually be really difficult.

I hate statics and hydrostatics, usually I find it impossible to just get a good force diagram and to get started on the q. We didn't cover q6. I expect a pretty hard exam, the only questions that are consistently easy are q3,5 and 10 imo.

Peregrine

I've no choice but to do 1-5 and 10. I know some of 7 but not enough for a full question

I like them all except RV - that I hate.

Nicke011

Can someone explain me why is t4+t6=t in question 1, b) iii) in 2011?

AtomicKoala

Nimrod 7 wrote: »

I've no choice but to do 1-5 and 10. I know some of 7 but not enough for a full question

I like them all except RV - that I hate.

Statics? Oh god don't do statics :pac:

CelestialKing

Nimrod 7 wrote: »

I've no choice but to do 1-5 and 10. I know some of 7 but not enough for a full question

I like them all except RV - that I hate.

That describes me perfectly, I know they're easy but damn those RVs... I NEVER get it fully out.

Ompala

Nicke011 wrote: »

Can someone explain me why is t4+t6=t in question 1, b) iii) in 2011?

It follows from there being same acceleration in part (ii) as in part (iii)
If it take t1 seconds to get to a speed v, and t4 seconds to get to a speed (2/3)v then for the same acceleration it must be true that t4 = (2/3)t1
A similar argument holds for t2 and t6, so that t6 = (2/3)t2
Then t4 + t6 = (2/3)t1 + (2/3)t2 = (2/3)[ t1+t2 ]
From part (ii) t1 + t2 = t so by substituting t4 + t6 = (2/3)t

WoolyAbyss

So I've decided I'm going to do pass I already have seven subjects and have done no study for this in months.
Anybody know how difficult ordinary is to pass? Question 1-3 OL look like you could do well in them if you were decent at mechanics in physics.

TheBegotten

Lads, seriously, what's with this weather? Two exams on Friday and I can't study with the heat. Anyway, what do people think of Q3? I'm not great at trigonometric manipulation, but it's normally a nice enough question otherwise. Would most of ye plan on doing it?

Nicke011

Ompala wrote: »

It follows from there being same acceleration in part (ii) as in part (iii)
If it take t1 seconds to get to a speed v, and t4 seconds to get to a speed (2/3)v then for the same acceleration it must be true that t4 = (2/3)t1
A similar argument holds for t2 and t6, so that t6 = (2/3)t2
Then t4 + t6 = (2/3)t1 + (2/3)t2 = (2/3)[ t1+t2 ]
From part (ii) t1 + t2 = t so by substituting t4 + t6 = (2/3)t

Got it! Thanks

TheBegotten wrote: »

Lads, seriously, what's with this weather? Two exams on Friday and I can't study with the heat. Anyway, what do people think of Q3? I'm not great at trigonometric manipulation, but it's normally a nice enough question otherwise. Would most of ye plan on doing it?

I'm doing 1,2,3,4,5,10 as majority of the people here if you need help, you can ask here

AtomicKoala

Are there any questions from certain years it'd be worth doing? I'm getting a bit bored here and feeling like I'm wading through an ocean :pac:

TheBegotten

Nicke011 wrote: »

I'm doing 1,2,3,4,5,10 as majority of the people here if you need help, you can ask here

I'm definitely doing 1, 2, 4, 9 and 10. It'll be a toss up on the day between 3 and 5. I'm surprised no-one's doing 9, I normally find that quiet easy.

PaleMoonlight

AtomicKoala wrote: »

Are there any questions from certain years it'd be worth doing? I'm getting a bit bored here and feeling like I'm wading through an ocean :pac:

My teacher has marked out questions for me to do which practices which type of question, what questions are you doing and I could message some on to you if you like?

AtomicKoala

PaleMoonlight wrote: »

My teacher has marked out questions for me to do which practices which type of question, what questions are you doing and I could message some on to you if you like?

Sure if you want to take a pic, but don't let me waste your time :eek:

I'm doing 1, 2, 3, 4, 5, 7, 8 and 10.

Nicke011

AtomicKoala wrote: »

Are there any questions from certain years it'd be worth doing? I'm getting a bit bored here and feeling like I'm wading through an ocean :pac:

I recon Mocks would be a useful one to do.

TheBegotten wrote: »

I'm definitely doing 1, 2, 4, 9 and 10. It'll be a toss up on the day between 3 and 5. I'm surprised no-one's doing 9, I normally find that quiet easy.

That's hydrostatics? I was told on the first day by my teacher that we are definitely not going to do it, because hydrostatics is the hardest question... That's why I always wanted to do it, or at least see what's so much hard about it but yeah, never had time... That's just how this educational system works.
I would very confidently say that she didn't know how to do them, so she didn't want us to try them.

PaleMoonlight wrote: »

My teacher has marked out questions for me to do which practices which type of question, what questions are you doing and I could message some on to you if you like?

Could you message me? That sounds like something really helpful and time-saving at this stage 1,2,3,4,5,10

Ompala

Nicke011 wrote: »

I recon Mocks would be a useful one to do.


That's hydrostatics? I was told on the first day by my teacher that we are definitely not going to do it, because hydrostatics is the hardest question... That's why I always wanted to do it, or at least see what's so much hard about it but yeah, never had time... That's just how this educational system works.
I would very confidently say that she didn't know how to do them, so she didn't want us to try them.


Could you message me? That sounds like something really helpful and time-saving at this stage 1,2,3,4,5,10

Your teacher is talking absolute rubbish, it is in no way the hardest question
In fact many times its been much easier than the popular questions
The reason its not widely taught is because many teachers have never studied it themselves

PaleMoonlight

TheBegotten wrote: »

I'm definitely doing 1, 2, 4, 9 and 10. It'll be a toss up on the day between 3 and 5. I'm surprised no-one's doing 9, I normally find that quiet easy.

I'm doing 9, but I personally disagree about it being the easy, depends on the question though. Sometimes it's lovely and other times its terrible.

Anyone else the only person doing Applied Maths in their school? Will be a bit awkward in the exam hall

wafture

PaleMoonlight wrote: »

My teacher has marked out questions for me to do which practices which type of question, what questions are you doing and I could message some on to you if you like?

I would also really really appreciate this please if you have time! I'm doing 1-5 and 10

mcratsix

TheBegotten wrote: »

I'm definitely doing 1, 2, 4, 9 and 10. It'll be a toss up on the day between 3 and 5. I'm surprised no-one's doing 9, I normally find that quiet easy.

Ewwww q9. Why not q3? That's like easiest q on the entire exam, in my opinion.

Nicke011

PaleMoonlight wrote: »

I'm doing 9, but I personally disagree about it being the easy, depends on the question though. Sometimes it's lovely and other times its terrible.

Anyone else the only person doing Applied Maths in their school? Will be a bit awkward in the exam hall

I actually prefer doing it when there are few or no people around me, it's much easier. I was the last one left in the classroom for two exams (for about an hour), and it wasn't awkward at all
Relax, and take your time... Don't think about getting out earlier because examiner has to be there anyway.

mcratsix

wafture wrote: »

I would also really really appreciate this please if you have time! I'm doing 1-5 and 10

If you go onto thephysicsteacher.com, you can get papers back to the early 90s. If you can do these questions, you'll fly the exam on Friday, they're a good 20% harder on average I'd say. However, if you're trying these questions and getting nowhere, then just leave them because it's a waste of time, and it'll just make you feel unnecessarily scared. But I'd try them and see.

TheBegotten

mcratsix wrote: »

Ewwww q9. Why not q3? That's like easiest q on the entire exam, in my opinion.

Can't do trig for the life of me. It's grand in maths, but the trig in applied maths, particularly question 3, is horrendous. I like question 9, the pressures and relative densities of mixtures and stuff comes pretty easily to me. Our teacher didn't do the circular motion or inertia questions, so we're limited to 1, 2, 3, 4, 5, 7, 9 & 10, and 7 is almost invariably the hardest on the paper.

mcratsix

TheBegotten wrote: »

Can't do trig for the life of me. It's grand in maths, but the trig in applied maths, particularly question 3, is horrendous. I like question 9, the pressures and relative densities of mixtures and stuff comes pretty easily to me. Our teacher didn't do the circular motion or inertia questions, so we're limited to 1, 2, 3, 4, 5, 7, 9 & 10, and 7 is almost invariably the hardest on the paper.

Leaving out moments of inertia is a big mistake on your teachers part, it's quite simple usually.

rocco123

Do the proofs for 8a have to be same as marking scheme or can they be from the book?

mcratsix

rocco123 wrote: »

Do the proofs for 8a have to be same as marking scheme or can they be from the book?

From the book is fine according to my teacher

qweerty

@mcratsix I thanked one of your posts, but I thoroughly disagree with your sentiments regarding Statics!

@TheBegotten I agree that some Q3s have had fiendish trig manipulations.

CelestialKing wrote: »

Last I checked it wasn't an originality test! If it was I'd be doing Hydrostatics. Has it really been that long for a wedge? I want one sooo badly! We didn't study RMB so I wouldn't know how easy it is, which Q is it normally on the paper?

I really need an A1. Don't know if I can pull it off. 2 days free before the exam though

This could be a rumour, but I heard from a guy who got 100% on every question that AM is the only subject apart from English that uses the PCLM marking scheme: only the ten percent for "mechanics" actually goes towards how "correct" your answer is. Therefore, I'd encourge that you try to be really original! Try things the corrector will neve have seen before, like da Vinci-esque mirror writing. Let me know how you get on

Now that I think about it, as well as RBM (Q8), RV can be pretty handy. None of the topics is especially difficult, but some of the q's can be, so when I say RBM is one of the easiest, I mean the questions have been pretty standard (plus the free twenty marks for the easiest-to-learn proofs ever to have been prescribed!!).

There was a point in the exam when I had to decide whether to abandon a q or keep hammering. I chose the former and ended up getting an A1. Having taken ages to get the answer on the way home afterwards, I guarantee you I would have got around a C if I hadn't moved on. I suspect loads of students capable of getting an A (and let's face it, AM more than perhaps any other subject, has loads of students who could get an A depending on how well the exam goes) fail to get one because of getting bogged down (actually, now that I think about it, that theory falls down considering how few cover more than seven topics ).

Rmember that most marks go for setting the q up. Carefully review every answer, cause sometimes correcting a small mistake can move you up a level in the MS resulting in your getting a chunk of marks. It's a complete disaster if you don't give every part a decent attempt. Rememer that a-parts are often equal to b-parts in term of marks. At this stage, I'd be going through past papers and answering them in my head.

Erm...anything else? Oh, sometimes bringing an extra teddy can pay dividends!

Good luck everyone. And don't feel any pressure because of the fact that I still judge people in college on the basis of their AM result! What?! I can't help it

otpmb

PaleMoonlight wrote: »

Anyone else the only person doing Applied Maths in their school? Will be a bit awkward in the exam hall

Last year my supervisor offered me tea when it was just me and him in the exam hall.

AtomicKoala

What are the chances of them asking a topic in a different question to the norm?

In 2002, Simple Harmonic motion came up in Q4(a). Has this happened elsewhere? :eek:

Delightfully Bright

AtomicKoala wrote: »

What are the chances of them asking a topic in a different question to the norm?

In 2002, Simple Harmonic motion came up in Q4(a). Has this happened elsewhere? :eek:

There would be uproar if they do something like SHM in Q4 but I can see them linking similar topics. Putting in an impact or a bouncing projectile into Q3 would make sense.
They know most students don't cover the whole syllabus so I can't see them destroying the bell curve just to test us.

Daniel2590

AtomicKoala wrote: »

What are the chances of them asking a topic in a different question to the norm?

In 2002, Simple Harmonic motion came up in Q4(a). Has this happened elsewhere? :eek:

Yeah it happens from time to time, just after doing a question in relative velocity that involved collisions.

AtomicKoala

This SHM question (2004 Q4(a)) had nowt to do with Connected Particles though, hence my panic. I've spent an hour learning the basics of SHM

Delightfully Bright

AtomicKoala wrote: »

This SHM question (2004 Q4(a)) had nowt to do with Connected Particles though, hence my panic. I've spent an hour learning the basics of SHM

Unless you're going to do SHM I don't think it's worth it. If they can randomly put SHM into a question, why not statics or moments of inertia? This is why it's good to have a spare question just in case they do through a curve ball like this.

Nicke011

Does anyone have results for Mocks questions? (1,2,3,4,5,10)
I'm not sure if it's DEB or Examcraft, so I'll write out question 1.

Q1. a) The maximum acceleration of a body is 9m/s^2 and its maximum ratardation is 3m/s^2. What is the shortest time in which the body can travel....
b) A car P start from a point O with initial velocity of 6m/s and then travels with a uniform acceleration of 3m/s^2. Three seconds later...

Thanks

Peregrine

Nicke, that's Examcraft. I haven't got the solutions though. Sorry.

PaleMoonlight

Nicke011 wrote: »

Does anyone have results for Mocks questions? (1,2,3,4,5,10)
I'm not sure if it's DEB or Examcraft, so I'll write out question 1.

Q1. a) The maximum acceleration of a body is 9m/s^2 and its maximum ratardation is 3m/s^2. What is the shortest time in which the body can travel....
b) A car P start from a point O with initial velocity of 6m/s and then travels with a uniform acceleration of 3m/s^2. Three seconds later...

Thanks

That's examcraft, I have my attempt at it with my teachers corrections, I'm not sure if it would just be confusing though?

Chonaic17

For the Wedges, can someone explain to me why the accelerations of the particles relative to the wedge are mthe way they are. i.e for the acc perpendicular to the slope. it is mgcos(theta)-R=m(asin(theta)). I know that's how it's done but I don't actually see where the m(asin(theta)) part comes from.

Ompala

Chonaic17 wrote: »

For the Wedges, can someone explain to me why the accelerations of the particles relative to the wedge are mthe way they are. i.e for the acc perpendicular to the slope. it is mgcos(theta)-R=m(asin(theta)). I know that's how it's done but I don't actually see where the m(asin(theta)) part comes from.

Its Newtons Second Law, F =ma
This is a little tricky to explain without a diagram but basically you splitting the acceleration up into horizontal and vertical components
I assume we are looking at vertical components here due to R being used in the equation, so the force, F = mgCos(theta) - R
Similar to how you split up the weight of the object, mg, relative to the wedge, you must do the same with the acceleration.
The acceleration in the vertical direction will be given by aSin(theta), so by Newtons Second Law you get mgCos(theta) - R = m(aSin(theta).

Chonaic17

Ompala wrote: »

Its Newtons Second Law, F =ma
This is a little tricky to explain without a diagram but basically you splitting the acceleration up into horizontal and vertical components
I assume we are looking at vertical components here due to R being used in the equation, so the force, F = mgCos(theta) - R
Similar to how you split up the weight of the object, mg, relative to the wedge, you must do the same with the acceleration.
The acceleration in the vertical direction will be given by aSin(theta), so by Newtons Second Law you get mgCos(theta) - R = m(aSin(theta).

Oh wow it just hit me there as I read this, thanks a lot that makes perfect sense.

mcratsix

Ompala wrote: »

Its Newtons Second Law, F =ma
This is a little tricky to explain without a diagram but basically you splitting the acceleration up into horizontal and vertical components
I assume we are looking at vertical components here due to R being used in the equation, so the force, F = mgCos(theta) - R
Similar to how you split up the weight of the object, mg, relative to the wedge, you must do the same with the acceleration.
The acceleration in the vertical direction will be given by aSin(theta), so by Newtons Second Law you get mgCos(theta) - R = m(aSin(theta).

The mgcos(theta) is the weight of the particle acting perpendicular to the slop, the R is the reaction of the wedge pushing up on the particle. Since the particle is sliding down the wedge, we know that the force acting down must be greater than the force acting up, hence we get mgcos(theta)-R and not R-mgcos(theta). The acceleration of the particle is usually just denoted as "f", so using f=ma we get mgcos(theta)-R=M(f-acos(theta). Similarly here, the "f" is larger than the acos(theta) so we arrange it this way.

It's difficult to explain without a diagram, as Ompala said. If you think of a simple weight on a pulley q. If the weight is falling down, we'd say, for example, 3G-T=3a, whereas if it were being pulled up, it would be T-3G=3a. Same principle.
Personally I really want a wedge q now, I think one is due as well.

Ompala

mcratsix wrote: »

The mgcos(theta) is the weight of the particle acting perpendicular to the slop, the R is the reaction of the wedge pushing up on the particle. Since the particle is sliding down the wedge, we know that the force acting down must be greater than the force acting up, hence we get mgcos(theta)-R and not R-mgcos(theta). The acceleration of the particle is usually just denoted as "f", so using f=ma we get mgcos(theta)-R=M(f-acos(theta). Similarly here, the "f" is larger than the acos(theta) so we arrange it this way.

It's difficult to explain without a diagram, as Ompala said. If you think of a simple weight on a pulley q. If the weight is falling down, we'd say, for example, 3G-T=3a, whereas if it were being pulled up, it would be T-3G=3a. Same principle.
Personally I really want a wedge q now, I think one is due as well.

On a side note, if ye are expecting a wedge, remember that if you have connected particles on the wedge, then you must account for the tension in the string when writing the equation of motion for the wedge. I think there is a question from around 1994 on this

otpmb

Oh, if you break forces up into horizontal and vertical components in q4 on your diagram make sure you do it in different colours (i.e the force in one colour and its' components in another colour) otherwise it's treated as a mistake because you've got the same force in twice. I know this because my teacher corrects the papers every year, and he warned us that loads of people lose marks over this.