A few of you have asked about turning in corrections for physics Quiz 14. If you have any to turn in, please bring them to the potluck.

Attached is a “revision edition” of the Physics exam. If you choose to submit corrections/revisions please do so using this version of the exam (which is “compressed;” you’ll need to answer on separate sheets of paper).

Download (PDF, 377KB)

One super last-minute reminder – we meet in the Library today, at 9 AM for the Physics exam (room 1001) and at 1 PM in room 1005 for the Math (and then Chemistry) exam revision workshops.

As a reminder, you will be allowed one 8.5″ x 11″ sheet for equations, etc. as well as a calculator (phone is OK) for the exam.

To further clarify what I mean with regard to whether DC circuits are on the exam, there is certainly material on circuits in other chapters than Ch. 25; in particular, I do expect you to be able to deal with power in simple circuits, Ohm’s Law, and the transient behaviors of RC and LC circuits. What I will not ask you to do is extensive circuit analysis or find equivalent values for components in series, parallel, and more complex configurations.

As a final reminder, you should bring any corrections from the last quiz, as well as your physics problem set notebook, to the exam.

Below is the “revision edition” of Quiz 14. There is no IDEAl problem with exams coming up. I’ll be returning Quiz 14 at the math exam.

Download (PDF, 86KB)

The physics schedule for Week 19 is virtually unchanged relative to a “normal” week. The only significant change is that the physics workshop will be Wednesday morning rather than Thursday noon.

This means that the usual weekly quiz still happens at 9 AM Wednesday, and will cover material from Chapter 26 of Wolfson.

The IDEAl solution for the week is based on, but different from, the back page of Quiz 13. Attached are the original quiz and the IDEAl solution assignment; your IDEAl solution answer can serve as corrections for the back page of the quiz, so you need not do both.

I do want to emphasize on the IDEAl solutions that you need to justify your formulas, if even briefly. You are being asked to calculate twelve values (Q, W and change in S for each of the 4 processes of a Carnot cycle); many are zero and the rest use formulas you can find in the text. You should be able to justify in a few words why each is applicable. For instance, if a process were isochoric you should know right away that W=0. Write something like, “W=0 because there is no volume change, and W=-integral (p dV)” Or if a process were isobaric, you should write, “W=-p(V_2-V1) (isobaric process)” rather than simply writing the formula alone. This is what I mean by justifying your use of a formula – by identifying in a few words the relevant physics of the situation. You have a bunch of formulas for work; you need to make it clear why you chose the one you did!

Download (DOCX, 65KB)

Download (DOCX, 1.23MB)

First, I will not assign a new IDEAl problem for this week. I owe you feedback and you need some time to work on poster drafts.

Second, as a reminder, the Week 18 quiz next Wednesday covers both chapters 18 and 19 from Wolfson (all the thermodynamics we have done in physics). Bear this in mind as you create your index cards.

This week’s IDEAl problem is a version of the last Quiz 12 problem. (I’ve reduced the number of parts, though I think you’ll find that the parts I removed just become intermediate calculations.)

If you submit quiz revisions, please use the version of the quiz posted here rather than the original version. The first page asks the questions in a different way that’s more appropriate to a second attempt.

Both files are here and in the appropriate physics handout sections of the program fileshare.

Download (DOCX, 50KB)

Download (DOCX, 19KB)

Here is a video on semiconductors devices and, in particular, the NPN transistor. In lab you will be building a version of the transistor switch (0:25-0:31 of the video).

I’d like you to watch through about 5:50 of the video (keep watching if you want a brief introduction to transistors used as amplifiers).