The Sum of the Forces tag:blog.lib.umn.edu,2009:/jaustin/classes//3078 2009-01-05T16:24:29Z Movable Type 4.25 Comments on grades tag:blog.lib.umn.edu,2009:/jaustin/classes//3078.161090 2009-01-05T16:12:11Z 2009-01-05T16:24:29Z Hello everyone- 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... Jay Austin Hello everyone-

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-


]]> Final and the weather tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.159706 2008-12-14T13:55:00Z 2008-12-14T13:57:16Z Unless the university is officially closed on Monday morning (there is no indication so far that this will happen) the final will run from 10-11:55 Monday morning as scheduled. There is another final in the room after us, so if... Jay Austin Unless the university is officially closed on Monday morning (there is no indication so far that this will happen) the final will run from 10-11:55 Monday morning as scheduled. There is another final in the room after us, so if you want the full two hours to work, please make accommodations to get to the final on time!

jay-

]]> Lab report reminder tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.159660 2008-12-13T16:55:57Z 2008-12-13T16:58:42Z Just a reminder- 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-... Jay Austin Just a reminder-

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-

]]> Practice exam key tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.159634 2008-12-12T22:35:25Z 2008-12-12T22:43:27Z Hello everyone- 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... Jay Austin Hello everyone-

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-

]]> Final key tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.159305 2008-12-10T21:10:10Z 2008-12-10T21:16:01Z I've posted the key to HW 14 online. For a change, I've posted no new homework. Whew. If people have suggestions of specific problems or types of problems they'd like to see covered tomorrow, please let me know ASAP so... Jay Austin I've posted the key to HW 14 online. For a change, I've posted no new homework. Whew.

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-

]]> Homework due tomorrow tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.159190 2008-12-09T22:36:42Z 2008-12-09T22:37:21Z Apparently I didn't change the due date on Homework #14. It is due tomorrow at the beginning of class. jay-... Jay Austin Apparently I didn't change the due date on Homework #14. It is due tomorrow at the beginning of class.

jay-

]]> Last Homework tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.158389 2008-12-05T22:56:45Z 2008-12-05T22:57:29Z The 14th and last homework for the class is posted now. See you Monday! jay-... Jay Austin The 14th and last homework for the class is posted now. See you Monday!

jay-

]]> Final Exam Schedule tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.158360 2008-12-05T19:52:49Z 2008-12-05T19:54:02Z The syllabus incorrectly states the time of the Final Exam. The final exam for PHYS2011, Fall 2008, is 10:00-11:55 on Monday, 15 December. We will meet in MWAH 195, as usual. jay-... Jay Austin The syllabus incorrectly states the time of the Final Exam. The final exam for PHYS2011, Fall 2008, is 10:00-11:55 on Monday, 15 December. We will meet in MWAH 195, as usual.

jay-

]]> error on the key tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.157612 2008-12-02T15:10:44Z 2008-12-02T15:17:23Z There was an error on the key for the last homework- unfortunately, the grader did not pick up on it. on 14.6, the book you have states that the area of a lid is 77m2. In the copy of the... Jay Austin There was an error on the key for the last homework- unfortunately, the grader did not pick up on it.

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-

]]> Homework 13 tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.157549 2008-12-02T02:33:19Z 2008-12-02T02:35:02Z On the written out problem on homework 13, I am only concerned with the amount the pond would heat up from the sun shining on it. Ignore all other heat transfer mechanisms. In the real world, there are other mechanisms... Jay Austin On the written out problem on homework 13, I am only concerned with the amount the pond would heat up from the sun shining on it. Ignore all other heat transfer mechanisms.

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

jay-

]]> A slight modification to HW 13 tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.157360 2008-12-01T17:07:39Z 2008-12-01T17:10:10Z Hello everyone- 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... Jay Austin Hello everyone-

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-

]]> Misprint on homework tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.156568 2008-11-24T22:01:07Z 2008-11-24T22:03:16Z I have a misprint on the homework due Wednesday- in the first problem, I define apparent weight to be the true weight of the object plus the buoyancy force- it should be MINUS the buoyancy force. Weight is a force... Jay Austin I have a misprint on the homework due Wednesday- in the first problem, I define apparent weight to be the true weight of the object plus the buoyancy force- it should be MINUS the buoyancy force. Weight is a force fdirected downward. You should find that the concrete blocks have a positive apparent weight (just like any of us have a positive apparent weight standing around in air) and the steel sphere float will have a negative apparent weight.

jay-

]]> Practice exam tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.155767 2008-11-20T21:23:51Z 2008-11-20T21:24:36Z The practice exam (with some annotations) is posted on the website. Also, a cheat-sheet for tomorrow's exam. jay-... Jay Austin The practice exam (with some annotations) is posted on the website. Also, a cheat-sheet for tomorrow's exam.

jay-

]]> Homeworks, keys, etc tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.155708 2008-11-20T17:48:29Z 2008-11-20T18:05:25Z Homework 12 is posted, as is a key to homework 11. 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/... Jay Austin Homework 12 is posted, as is a key to homework 11.

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 stuff posted tag:blog.lib.umn.edu,2008:/jaustin/classes//3078.154393 2008-11-13T19:01:27Z 2008-11-13T19:02:59Z Hello everyone- 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... Jay Austin Hello everyone-

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-

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