Since I've received a lot of inquiries regarding final grades, I just thought I'd make a few comments here- Hopefully these comments are still in some of your RSS feeds and you'll see these comments.

I am not going to post the exact cutoffs between A/B/C/D/F- suffice it to say that they are lower than the 90/80/70... cutoffs I posted on the syllabus (that's to your advantage). You have enough information to determine your final score given the information in e-gradebook.

The average grade (~74) and the median grade (~75) fell squarely in the 'C' range, where they should.

I try very hard to be absolutely fair about how grades are determined- with the exception of determining the cutoffs (over which I retain a small amount of discretion), determination of grades is entirely objective and follows the weighting scheme laid out in the syllabus. Indeed somebody in the class got the highest B+ and missed an A- by a fraction of a point; at the same time somebody got the lowest A- and missed getting a B+ by a fraction of a point. This is one of the unavoidable consequences of discretized grading schemes.

jay-

jay-

please get any outstanding lab reports to your TAs by Monday AT THE LATEST. I'd like to be able to get the grades posted for the class ASAP.

jay-

I've posted a key to the hot air balloon problem we did yesterday, as well as to the practice exam we worked on today.

I managed to pretty badly mangle things on the second problem of the practice exam today, as several of you pointed out. I over-specified information in the thermodynamic cycle problem, so that the problem was internally inconsistent. I've revised the problem and written up a solution. I rushed preparing the problem this afternoon before class and I didn't think it through thoroughly. I apologize for the oversight and hope that the explanation in the key will assure that you come out of the practice exam experience more, rather than less, prepared for the exam.

With regards to studying: The cumulative multiple choice part of the exam covers kinematics and linear dynamics (no rotational dynamics or statics). It really focuses on your conceptual understanding of concepts like velocity, acceleration, force, momentum, energy, and the relationships between these. It doe not call for a calculator.

The rest of the exam is a bit more traditional. It will cover fluids, temperature and heat (and the relationship between them), the First Law of thermo and ideal gases. One of the problems asks for an explanation rather than a calculation; the rest are fairly straightforward (and well-posed) calculation problems.

See you Monday, 10:00, in MWAH 195!

jay-

If people have suggestions of specific problems or types of problems they'd like to see covered tomorrow, please let me know ASAP so I can work something up.

The final exam will consist of two parts:
1. A 26-question multiple choice test, similar but somewhat more quantitative than the diagnostic you took earlier. This focuses heavily on the basic concepts of velocity, acceleration, force, energy, and momentum.
2. Problem solving, covering fluids at rest (hydrostatics/buoyancy/etc), heat and temperature (specific heat/heat content and heat transfer), the first law of thermo, and ideal gas law stuff.

jay-

jay-

jay-

jay-

on 14.6, the book you have states that the area of a lid is 77m2. In the copy of the text I have at home (must be a different version) it states it as 77cm2, which makes a lot more sense for a lid of negligible weight. As you might imagine, this makes a great deal of difference to the answer. Since I'm guessing the grader took a point off of everyone's paper for an incorrect answer, I'm going to put one point back on everyone's HW12 (who turned it in), to save the trouble of digging through all of the assignments again.

I will post an addendum to the key.

jay-

In the real world, there are other mechanisms at work as well, of course.

jay-

I don't like the order the book presents the material in this chapter, so I'd like to discuss heat transfer mechanisms (18.12) today, and postpone the first law of thermo (18.9-18.11) until Wednesday.

Therefore, I'd like to postpone HW problem 18.46 until the next homework. In it's place, please solve 18.57. If you've already done 46, hold onto it and turn it in with HW 14.

jay-

jay-

jay-

I've recently seen three videos which all look like great exam questions. Take a look at these, and think about the physics (or lack thereof) behind these:

http://failblog.org/2008/11/19/shopping-cart-fail/

http://failblog.org/2008/11/18/logistics-fail/

http://failblog.org/2008/11/17/cable-fail/

jay-

Homework 11, and the key to homework 10, are now posted on the website.

In answer to several people's questions: yes, there's an exam next friday. It will cover rotation and statics.
We'll discuss it tomorrow and hopefully we'll be able to fit in a practice exam.

jay-