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AQA A2 MM2B Mechanics 2 – 27th June 2016 [Exam Discussion Thread]

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I just did June 15 as a mock and only just got a B. Time was an issue but didnt eve know how to start the last question. Been getting A* in all past papers apart from in this one I just crumbled. I don't like a question where it is 8/9 marks and asks you to calculate something straight up instead of leading you into it with different parts. Anyone got any tips? after the way my other maths exams have gone I really need to do well on this. M3 is the worst exam I have had so far.

Reply 81

Pentaquark

Getting mostly A*s (90UMS+) in past papers but I feel like I'm going to crumble tomorrow.
Like doing past papers at home is so much easier. :s
Anyone else in a similar position?!
I just want an A* but I feel like the paper tomorrow will be absolutely horrible.

I'm predicting lots of algebraic manipulation and quite a few large mark questions with no parts.
I mean M1 wasn't too bad but there were larger mark questions and less parts.

I couldn't even do the question that requires the double angle formula as I thought I only needed to know simple stuff from C3 like
differentiating & integrating sin, cos, ln, e & separating variables. :angry:

Good Luck everyone anyway!
Hopefully it will be hard in a good way so that the grade boundaries will be nice.

Reply 82

Hjyu1

I am so scared about meeting my offer I bombed 2 of my other exams so this exam is literally make it or break it for me and seems like it is for other people

Reply 83

Jm098

Original post by JPencil

I'm about to do 2015 as a mock. I'm actually looking forward to D2, from the bits I've done it seems nice. Do you know if we have to use simplex to find optimal mixed strategies?

Yeah it's okay, and no we don't but that would be useful! Game theory is the best topic imo

Reply 84

C0balt

Original post by Hjyu1

I am so scared about meeting my offer I bombed 2 of my other exams so this exam is literally make it or break it for me and seems like it is for other people

Agreed

Reply 85

sam_97

Original post by Pentaquark

Good Luck everyone anyway!
Hopefully it will be hard in a good way so that the grade boundaries will be nice.

I'm the same as you. I hardly drop any marks when doing past papers at home, but I can't seem to perform quite as well in real exams. I guess it's just exam pressure.

Reply 86

sam_97

Original post by Hjyu1

I am so scared about meeting my offer I bombed 2 of my other exams so this exam is literally make it or break it for me and seems like it is for other people

I know the feeling

Reply 87

Pentaquark

Good Luck especially to everyone who is banking on this exam to meet their uni offers!
Gosh I don't think I could cope with all that pressure! :frown:

I'm glad I'm an AS student right now. :colondollar:

I can't complain haha

Reply 88

misslili118

HELP QUESTION 8 JUNe 13 PART B

Reply 89

sam_97

Original post by misslili118

HELP QUESTION 8 JUNe 13 PART B

Using conservation of energy, we know that:

\frac{1}{2}m(v_Q)^2 = \frac{1}{2}m(v_S)^2 + mg\Delta h \:\: \therefore \:\: \frac{1}{2}m(v_S)^2 = \frac{1}{2}m(v_Q)^2 - mg\Delta h

We can now cancel all the

m

terms and tidy things up a bit:

\frac{1}{2}(v_S)^2 = \frac{1}{2}(v_Q)^2 - g\Delta h \:\: \therefore \:\: (v_S)^2 = (v_Q)^2 - 2g\Delta h

From the information given in the question, we know that

v_S = 5u

. We can also work out the value of

\Delta h

(the vertical distance between Q and S) using a bit of simple trigonometry. It turns out that

\Delta h = a + acos 60^{\circ}

. Therefore,

(v_S)^2 = (5u)^2 - 2g(a + acos 60^{\circ})

(v_S)^2 = 25u^2 - 2ag(1 + cos 60^{\circ})

From part (a) we also know that

u = \sqrt{\dfrac{4ag}{21}}

. Hence,

(v_S)^2 = 25\bigg(\dfrac{4ag}{21}\bigg) - 2ag\bigg(\dfrac{3}{2}\bigg) = \dfrac{100ag}{21} - 3ag \:\: \Rightarrow \:\: (v_S)^2 = \dfrac{37ag}{21}

Resolving radially at S,

R = \dfrac{m(v_S)^2}{a} - mgcos 60^{\circ}

R = \dfrac{m\bigg(\dfrac{37ag}{21} \bigg)}{a} - mg\bigg(\dfrac{1}{2}\bigg) = \dfrac{37mg}{21} - \dfrac{1}{2}mg \:\: \Rightarrow \:\: R = \dfrac{53mg}{42}

(edited 7 years ago)

Reply 90

username1824647

june 15 Q9 taking moments about P i don how the distance between W (mg) and P is acos30
anyone???

Reply 91

Bobjim12

Feeling quite good, only thing i'm not 100% on is vertical circles and a bit of the good old springs, hopefully the questions that come are straightforward on these topics, so many method marks so i should be fine if i mess up signs and what not.

Reply 92

xFluorescent

Can someone help me with June 2006 Q5 part (a) and (d) please? Thanks.

Reply 93

snimkar

Original post by TheLifelessRobot

Does the reaction force always act towards the centre?

Depends if you are resolving radially or not. Usually given in the context of the question but if it was say a 8 mark question you would have to figure it out yourself.

Reply 94

rainbowtwist

Original post by Pentaquark

Good Luck everyone anyway!
Hopefully it will be hard in a good way so that the grade boundaries will be nice.

When is/was the double angle formula required? (and what is it -fellow year 12 😄)

Reply 95

Pentaquark

Original post by rainbowtwist

When is/was the double angle formula required? (and what is it -fellow year 12 😄)

Jan 13 - last question.
hemispherical bowl thing and you had to take moments.
It was a show that question.
tbh I don't understand it lol but its only like one mark lost I think ?

Reply 96

jjsnyder

Good luck to everyone tomorrow. If the problems are very difficult think hard that there's only a select few things that they will ask you on in given questions. Think about what topic it is then apply anything you know about that topic. Lost on a moments question? Resolve vertically/horizontally/parrellel/perpendicular and take moments about a point. Even if you don't get the answer you will get a lot of method marks! I probably won't be doing an unofficial MS after the exam as I am leaving school straight after, but if no one else does I'll contribute some answers. Again best of luck to those of you who have university offers depending on this exam, keep as relaxed as possible and try your best, you will pick up more method marks then you might think :smile: