Final grades

My flight leaves in <8hrs, so I'll be brief ...

• MasteringPhysics grades should be up to date. Check your lab scores carefully.
• Each HW is calculated as a percentage (they don't all have the same number of points), and the lowest two dropped. The rest are averaged. If you just added up total points, you may have gotten a different result.
• I scaled exam 3 to have an average of 80% instead of 73%, so you all gained some points.
• Final grades are on myBama now. Some of you got the benefit of the doubt with regard to +/- grades if you were on the borderline ...
• I'm happy to answer any questions you have about grading, just send me an email.
• I'm back in town on 8 July if you want to see / go over your test.
• If you're continuing on with PH102, I will have a sub (the guy teaching the 2nd section) covering the first two classes next week. Check out ph102.blospot.com for course info, notes, and the calendar. We'll use MasteringPhysics again, course id LECLAIRPH102.

Don't hesitate to email me if you have some questions ... I didn't intend to post final grades and run, but it sort of worked out that way! I will have email access while away though.

Grades

All grades (except the SHM lab from last week) should be up to date now. There is also a new column in Mastering Physics listing your overall grade as of right now, which includes dropping the lowest 2 homework sets and the lowest lab.

Keep in mind you have 1 homework and 1 lab yet to come, as well as one more exam.

Monday's lab

Monday, we'll verify Boyle's law. The lab is relatively short, which will leave us time to do the post-assessment test (and still probably finish early).

Additionally, if you would, please fill out this survey from the textbook publisher. Small price to pay for free textbooks, right?

Exam 2 scores are up

Lab scores have not yet been revised, that will be done (and the last lab's scores added) later today. Tonight, I will have some practice problems for exam 3 up hopefully. The last HW set is good practice material for the exam ...

Thursday's lab

Thursday, for our second-to-last lab, we'll investigate simple harmonic motion. Specifically, we will let little masses bounce on springs and measure bouncing as a function of time. If all goes well, the motion will match the theory we discussed earlier this week.

Grading update

A few more grades are in, as well as some updates.

• The problem solving competition grades are in. I grossly underestimated how seriously you would take this, so the class average was ~102% ... you win this round! In retrospect, I should have set the grading scale higher, but it was an experiment ...
• The collisions lab scores are in too.
• I updated almost all of the revised lab grades, except for a few of you, so most everything should be current now.
• Since the labs were entered as a % score (up to 100 points) and the homework as a number of points (9 to 11 points per homework set), I realized it is probably hard for you to gauge your current grade. I therefore multiplied all the homework scores by 10 to make them comparable to lab scores. Your lab average and homework average have equal weight, as do each of the exams. Keep in mind I drop the lowest 2 homeworks and the lowest single lab.
• To calculate your grade right now, drop the lowest 2 HW sets, and average the rest. Drop the lowest lab grade, average the rest. Take those two averages, and add in your exam 1 score. Divide by 3, and that's your current grade. After exam 2 scores are in, add your averages and both exam scores, and divide by 4 ... 
• If you'd rather I just tell you your grade, I have up-to-date overall grades, just ask or send me an email. So far as I can tell, MasteringPhysics does not let me put in an overall grade column to make this easier.
• Right now, the class average is a solid B. More than half of you have A's or B's at this moment. Very few of you are in any danger whatsoever of failing. After exam 2, nearly 75% of your graded work will be in.

And, to head this off ... I hope to have your second exam graded by Friday or Saturday, and will post grades as soon as they are done. 

Monday's lab

We'll investigate torque & angular acceleration, or 'rotational dynamics.'

Grade revisions

I've posted the lab 5 (work-energy) grades on MasteringPhysics now, as well as changes to some earlier lab grades for those of you who asked me to have a look. Please have a careful look - be sure that your lab grade matches the one written on the report you got back, and that your grade is the same as your group mates'. Same goes for the exam grades, do check that everything seems to be correct.*

The scores from today's problem solving competition should be ready tomorrow (Thurs), and I'll post the scores by team number here for the curious. It was a bit more chaotic and slower than I had imagined (as always), but I liked that you were engaged and putting in a good effort. You can leave (anonymous) comments here if you have thoughts on the competition, particularly how to improve it or if you'd want to do it again (modulo improvements).

* I try to be very obsessive and careful, but already at this point there are 340 lab grades alone to manually enter, and typos happen. This is something you should do in all your classes, in my opinion - anyone can make a mistake, now and again, so you should keep track of your own grades as best you can to make sure nothing seems off. There is absolutely nothing wrong with asking a professor to explain their grading calculation, that level of transparency should be considered mandatory. I don't mind at all if you question my numbers, and will happily explain them, I don't want them incorrect any more than you do.**

** If you notice an error in your favor, it is your call to mention it or not. I consider it your lucky day, and a lesson that I should be more careful. I don't expect you to bring it up, and don't fault you for taking the 'bonus.' If your conscience is eating away at you, however, then by all means let me know ...***

*** As we're on the subject of grading: I will add a column to MasteringPhysics shortly listing your overall course grade. You can ask/email me at any point for a grade update, I have them already calculated at any given moment.

Lab for Wed 15 June

Here's the lab for tomorrow, verifying the equations we came up with for 1D elastic and inelastic collisions

Wednesday's lab: problem solving 'competition'

Tomorrow, I thought we'd try a little problem solving competition. Here's a sketch of the idea. It worked pretty well when I tried it in the past.

Lab 5: work-kinetic energy

Here is the procedure; sorry for the delay. It uses the same half Atwood machine as last time, so the mechanics of the procedure are very similar.

Wednesday, we will have a team problem-solving competition, so there is no procedure you need to read. Just show up with a calculator, a notebook, and all of your cleverness.

Things

Exam 1 scores are now on Mastering Physics. The average was 81.7% with a standard deviation of 16.0%. I was pretty much happy with this ... you'll get the exams back on Wednesday.

Lab 3&4 scores are now on Mastering Physics. I have not yet adjusted scores on labs 1 & 2 for those of you that handed them back to me for regrading.

The HW4 deadline is extended through Tuesday, since I'm out of town anyway. HW5 will follow soon.

No lecture tomorrow (Mon) or Tues, but there is a lab as scheduled on Monday afternoon/evening.

Lab grades, once more

A couple of quick notes about lab reports:

• I have asked the grader to be explicit about what he is taking off points for.
• If you are unhappy with your lab report grade(s), bring me the reports tomorrow or Friday, and I will review them myself. If I think you've been shortchanged, I'll give you some more points. 

After getting some feedback from the TAs, I think we can be a little more lenient for the first few labs, since I think a lot of you didn't realize that you had to answer any questions asked in the writeup (and we could have been much more clear about that).

From now on, though, read the writeups carefully. For example, if the writeup says something like "Plot velocity versus time, and from its slope determine the acceleration. How does it compare with the prediction of Eq. 1?" There are three graded items here: we're expecting a plot of velocity versus time, a number for the slope and a comment on how the data compare to Eq. 1.

I guess in short, if something in the writeup is phrased as a question, it is pretty much never rhetorical. This is probably confusing because textbooks do usually pose rhetorical questions.

Last thing, I will try to just make the questions in the writeups more obvious. That will not replace carefully reading the whole thing as your best ally, but it should help ... 

Lab 1&2 grades

I've entered your lab 1 and 2 grades into the Mastering Physics gradebook for you to see. You should get those lab reports back today or tomorrow. A few thoughts:

• if the lab average is very low, I will scale it at the end of the term.
• if we ask a question in the lab writeup, it counts toward your grade
• if we ask for specific data or a plot to report, it counts toward your grade
• we do drop the lowest lab grade for the semester
• labs are worth 20% of your grade; while a merely low lab grade will not jeopardize your grade very easily, not going to the labs at all is a very bad thing.

I haven't seen the lab reports (I do not grade them myself), but I suspect some of the lower scores were due to handing in data but not answering the questions in the lab writeup. So, make sure you read the thing carefully and answer any questions asked at the beginning, along the way, or at the end ...

If you have questions about how the lab reports are graded, or feel like you lost points for something you shouldn't have, feel free to come see me. 

Today's lab ... revised

Due to a scheduling mix-up with the PH105 class, we'll do the friction lab today, and force on Wednesday.

Here is the friction lab writeup.

Monday's lab is now ready

Here you go. I had originally posted the labs out of order; this lab for Monday is on analyzing the force in an "Atwood's machine," a simple device with two masses and a pulley. We'll go over the analysis in class as an example problem.

Monday's lab

Tomorrow, we'll do a lab on force. I hope to have the procedure posted in an hour or so, I'm afraid I'm a little behind. To make up for not having allowed much time to read it, I will go over the gist of it at the end of class tomorrow.

[Update: I had the labs out of order. We'll do friction on Wednesday, and a different lab on force on Monday.]

Lab 2 bugfixes

Same link as before.

I found one mistake in the introduction (equation 7 had some extra bits), and the experimental procedure is now much more detailed.

If you've already read the procedure as I posted it earlier, you may not notice anything different, since the major changes were in the step-by-step procedure that isn't relevant until you're actually in the lab anyway. So ... you don't need to re-read the whole thing, but you might want to look around Eq. 7 if that part didn't make sense before.

Intro to Lab 1 slides

Here are the slides I used in the introduction to the lab session for the afternoon session, if you'd like to review them. (I was not there for the evening session with Mr. Davidson, but his introduction was going to be very similar ...)

If we have a little time in tomorrow's lecture, I'll do a re-cap of the lab and what the main points were. Specifically, what sort of analysis techniques wil be useful later on.

Lab 2: falling objects

I've got a draft of the lab 2 procedure up now - we'll analyze the motion of a falling object and learn how to calculate best-fit trendlines (linear regression). I will probably make some minor adjustments before Thursday (complete by Wednesday evening), but the gist of it will remain the same.

If I do make any changes, the link above will remain the same - I'll just replace the file. Please have a read through at least the introduction/background before Thursday's lab session.

Also, here's a nice applet related to linear regression you might find useful in understanding the lab analysis.