MAM1042S Q&A 2016

The situation is very fluid and circumstances could change. We are trying our best to make reasonable plans. If the situation changes, the plans may have to be adjusted. We are hoping January will go as smoothly as November did.

These answers apply to this course only. This page will change as more questions are asked.

Results

Results.

When will we get our results?
Since the course assessments are not complete, we don't have a final mark to publish. Effectively, those of you who wrote in November have written one out of two exam papers. The external examiner will only review the marking in February after all exams have been written. We request that you be patient. Focus on preparing for your remaining exams and getting as good a mark as possible.

Admin

DP, Final Mark, Mini semester.

Who gets DP?
Under the present circumstances, where only one test was written, we will allow a DP for all students who wrote test one, or submitted a medical certificate for test 1.
Will there be a "mini semester"?
Yes, and it will include an exam.

UCT has now announced a "mini semester" in early January. The EBE mini semester will run from 9th Jan for about 2 weeks, and EBE will inform you of the details. The Statics component will cover two of the four omitted topics: Compound systems (6.1 & 6.2 in the course text), and Integrating moments of inertia (8). There isn't time to cover Trusses (6.3), or Integrating distributed forces (7). There will be lectures and tutorials, and there'll be a short exam on the mini semester material. The exam will be written in the same exam session as the deferred exam, mini semester exam first, deferred exam second.

See below for how the final mark will be calculated.
When is the mini semester exam written?
The mini semester exam will be written in the same exam session as the deferred exam. The mini semester exam will be written first, those who wrote in November will leave, then the deferred exam will be written.

How will the final mark be calculated?
The EBE Faculty is considering ways of completing material that is essential for follow-on courses, which may include some assessment. Consequently, the composition of the final mark is not yet finalised. We do plan to use the test 1 mark and the exam mark, but there may be another component.

Final Mark (%) = Max Of
	Test 1(%) x 0.2	+	November/January Exam(%) x 0.56	+	Mini Semester Exam(%) x 0.24
	Test 1(%) x 0	+	November/January Exam(%) x 0.70	+	Mini Semester Exam(%) x 0.30

Will there still be a 40% exam subminimum?
. Yes - on the COMBINED November/January Exam + Mini Semester Exam. Here's an example

Individual marks:	Test 1 95%, Nov Ex 45%, Mini Ex 25%
Combined exam mark:	45% x 0.7 + 25% x 0.3	= 39% (below subminimum)
Pre-final mark:	95% x 0.2 + 45% x 0.56 + 25% x 0.24	= 50.2%
Final mark:		= 49% (fail since subminimum not reached)

In practice, students almost never get such low exam marks after such high test marks. You should be aiming to pass your exams anyway!

Will the test 1 re-scaling be retained?
Yes. BUT, as you know from the UCT announcement, the CR will not "pull down" your final mark. This will make the test 1 mark irrelevant in many cases. Get a good exam mark, and there's nothing to worry about!

(We were originally expecting there to be a test 2, and since it's on less basic material, marks are often lower on test 2 than on test 1. We were going to look at the marker averages again, and we thought a scaling up was a possibility. This of course did not happen.)

The Exams - What to Expect

Coverage, Differences from previous exams.

What material will be covered in the November 2016 exam?
Chapters 1 - 5 of the course text (including all the appendices); tutorials 1 - 9, but not including compound systems on tut 9. Material not covered includes general coplanar compound systems, trusses, integrating distributed forces, and integrating moments of inertia (area moments and mass moments).
What is the format of the November 2016 exam?
2 hours, about 8 questions. Marks on question paper > "full marks", as usual.
How will the November 2016 exam be different?
Only the material covered will be different. The exam questions will be very like those of past papers, but not including certain sections - see the question on coverage. There are many past papers available on Vula.
Will the January 2017 exam differ from the November 2016 exam?
The two exams will have the same coverage and format. Obviously the questions will be different. Seeing the November 2016 paper will not help you guess what's on the January 2017 paper.
What material will be covered in the mini semester exam?
Sections/Chapters 6.1, 6.2 & 8 in the course text; tutorials 9 (compound system questions), 10 & 13. Tutorial sheets will be put on Vula after the November exams are over. Be aware that these sections assume you are familiar with the earlier, more basic sections of the course.
What is the format of the mini semester exam?
50 minutes, 2 questions, the questions will have parts. It will be written immediately before January/February exam, in the same exam session. See above about the mini semester.
Will the exam marks be rescaled according to marker averages?
In the exam, markers mark only certain questions, and each question is marked by only one marker. This way, all scripts get the same treatment, and rescaling isn't necessary. This process is too hard to organise in tests (there are usually more markers than questions).

Tutorials

Getting help with specific tutorial questions.

Will there be tuts?
As was announced to everyone, help sessions have been set up at College House - see the sign-up in the Vula left menu. Otherwise, face to face teaching is currently (late 2016) not feasible. Feel free to ask your questions via Vula Q&A or Vula chat, and answers will be put on this Q&A page. (If there is a practical way to run tuts for sufficient numbers that won't be disrupted, we're open to suggestions! Make them via the Vula Q&A.)
Can we get tut solutions?
Not full solutions - they don't exist. All tut questions have answers, and there are hints - which give the method and step you through - for all group tut questions and some home tut questions.
If you want problems with full solutions, see the course text examples, the past test solutions, and the examples solved in class - there are plenty of them.
The tutorial questions are exercises for you to work on.
If you need help with a particular tut question, come to one of the help sessions, ask via Vula Q&A or Vula chat, and we'll try to give you hints and pointers in this Q&A.
Can we get past tuts online?
Tut sheets 1 to 9 have been uploaded to Vula Resources.

Tut 6, Q 9

- Use trig to get the *horizontal* distances between the CG, B and M.
- At B, the table is tangent to the spherical surface, and the normal reaction is perpendicular to the table.
- The normal to a tangent (to a sphere or circle) is .....? .......... radial. (Used quite commonly.)
- Are the 3 forces concurrent or parallel?
- Use moments to get M.

Tut 7, Q 5

- Above diag is for front wheel drive vehicle.
- Friction on driving wheel is tractive force, and it's forward. Friction (rolling resistance) on free wheel is very small (negligible) & backwards.
- Acceleration is obviously parallel to the slope & forward.
- Add distances to above diags.
- Moments about B on left diag = moments about B on right diag. Remember to include both components of the weight. This should give N_A, which contains a.
- [ Moments about A on left = moments about A on right. This should give N_B (not essential). ]
- For max accel, friction at driving wheels (= tractive force) is max.
- Resolve parallel on left = resolve parallel on right. Solve for accel a.

Tut 8, Q 10

- For bird as far right as possible,
     rod about to slide down at B, up at A,
     so frictions forces are in directions shown.
- Add bird's weight.
- Where is the concurrent point?
- Let rod have length s (= 1 m) and let bird be distance x from A.
- Figure out the angles at A & B.
- Use trig to get x.

- For bird as far left as possible,
     reverse directions of friction forces & repeat process.

- The two x values give the required range.

Theory - Lectures & Text

Questions about principles & methods, Clarifications of text material.

Will class example solutions be uploaded?
It was intended that there were some advantages to coming to lectures and taking notes.
There are fully worked examples in the text, but different ones in lectures.
It would not be possible or desireable to upload the lot.
However, if you want to ask about a specific example, we can possibly post some hints.

Past Papers

Getting help with questions on past papers.

Will the November 2016 paper be available online before the january exam?
This is not normally done. The January students should be in roughly the same situation as the November students were.