Final Exam Sample Questions (more, these aren't the first)

 

The file includes answers at the end to all the non-circuit questions.

More Chapter 19 and 20 Practice

 

Including my favorite: The Velocity Selector. The order of using the three Velocity Selector documents is vital here: It's Velocity Selector Solution Breakdown first. NO looking at Velocity Selector Lecture Problem until Velocity Selector Solution Breakdown is COMPLETELY used and filled in. Velocity Selector Lecture Problem is done as if it were a test in order for one to measure how well the Solution Breakdown document was comprehended.

 

The Velocity Selector covers three major review areas of the semester: Chapter 19, Chapter 15, and applying Newton's Laws and free-body diagrams in general.

 

Question: why do north poles repel other north poles? Unlike the question, "Why do positive charges repel other positive charges," this question can be answered. Figure out its explanation. One of the papers attached yields the phenomenon that explains pole interaction. (It would have to be a Chapter 19 paper, because poles are used in Chapter 19.)

Final Exam Topics Document

 

To help with the challenge you see posed in this document, I've posted some Chapter 19 Study Guide material. I imagine I may post a bit more on Jan. 7.

 

Taking too long to get this circuit rubric posted. People can delay the 2nd Circuit Quit until Jan. 10 if they like.

Circuit solution on paper (like a test) will be this week, Friday 12/21.

Those who plan to start vacation early and are missing Friday have to schedule a time to do it on Thursday.

 

The Advanced Landing the Plane calculation on Monday was a bit like this test. I have attached the key spreadsheet from Advanced Landing the Plane to this message for your convenience. Pay close attention to the meaning of the two rows called "5" and "Check on 5". This illustrates, once again, how any circuit solution can be checked for internal consistency.

You Are Doing This In Period 5 On Friday 12/7/18:

 

The attachment

 

The assignment is due upon arrival on 12/11/18, including the solution to the theoretical problem at the end.

The Book Solutions I promised

 

In class, I said there would be 9, 16, and 66. I misread my file names. There is no problem 16 solution written up by me (yet).

Key!

 

I've posted my answer to the E Field Vector Addition example tasks I handed out as hard copy on Wed. 11/7. This one had a positive and a negative charge at the base of an iscosoles triangle with a +3 nC charge at the upper vertex. The attached file has the answer to the first of the examples on the handout. Practice it on your own before looking.

 

Also, Ruby's day for Science is Friday 5 to 9. Extra credit available.

Notice on What's "due" Monday:

 

Principle of Superposition Notes: As I said in class, some subset of that is for HW, and I said to watch online. I hope in the meantime you've done your best with the document as written.

 

Something you don't know: In an ideal world that Superposition Notes document would be perfectly self-explanatory, as I try to make all of my notes. But in this case, there are a few places where the notes refer to some background knowledge that I did cover in class but it would be good if I had done so with some repitiition. I have now fixed that by adding an identical document but which includes a few addenda. (I was too hard on myself when I originally posted Friday that these addenda would be needed. Everything had been stated in class. My addenda just reiterate where needed.) The original document just moves pretty fast through some of the proportions. My addenda break these things down with a few extra steps. In bold.

 

To summarize then, as of Sunday afternoon, 3:05 PM 11/4/18: Now posted is a version of the original document as handed out in class but with bold-font elaborations of how what's in the document connects to what I said in class. You'll see that everything was stated in class, but I just elaborate more in places where it's bold. And it's not in that many places so maybe the original version of the document was just fine.

 

Long story short, here's what I hope people know on Monday:

1) The two physical quantities that E field depends on in the vicinity of a point source charge.

2) For a given E field, in N/C, what fraction or multiple you multiply that number by when the distance changes by the factor N. For example, if N is 1/9, what does the E field change to? (The answer is "It increases by a factor of 81.")

3) For a given E field, in N/C, what fraction or multiple you multiply that number by when the source charge changes by the factor M. For example, if M is 8.3, what does the E field change to? (The answer is "It increases by a factor of 8.3.")

4) Readiness to apply the two bits of proportional reasoning above (for any values of M and N) into an E field calculation problem.

5) Awareness of how to consider a point in space and calculate the total E field there when the E field is caused by two separate point charges that are at two different locations in the vicinity of that point in space. This is what the Principle of Superposition is.

6) Strong ability to set up #5 when the E field vectors are pointing along the same axis. For example, if a 3 C point charge is 4 m to the left of the origin and a -6 C point charge is 6 m to the right of the origin, how do you perform vector addition to get the total E field at the origin. (This is the E field at the origin due to the presence of both charges.) Answer hidden below.

 

Anyone who has used the document that I handed out on Thursday (11/1) (and re-attached here) should recognize that the 6 items above are quite a bit simpler than the entire document and the document more than covers all 6.

 

The little bold-font additions I've added as addenda to the document are intended to highlight items 2, 3, and 4 even more loudly.

 

By the way: you can look up Superposition Principle in Chapter 15 of the textbook. It's also called Electric field vector addition. The book is good.

 

 

 

Answer to the example embedded in Item 6 above: It's the following two rightward vectors added together: 1.5 GigaNewtons per Coulomb and 27/16 GigaNewtons per Coulomb. So the compact answer is 3.1875 GN/C rightward. (And if someone's not willing to look up Giga on one's own, they expect no high grades in physics class. I have to write it that way in this forum because the text tool doesn't do exponent notation.)

Active Practice is necessary for the test that's on October 30

Heads up for the weekend of 10/21/18:

 

The answer is posted for the advanced Stirling Engine cycle problem presented in class. This problem is close to the mastery level for Chapter 12 and you were instructed on what to solve in class. And a very clean word document that describes the problem is now attached. It's one page.

 

Latest versions posted here: former/latter typos are eliminated in the word document, but more importantly some key answer values are changed in the word document, because the gas is diatomic, Also, the spreadsheet is now as good as can be and also reflects the change to diatomic. One can now enter any values of n, m, p0, and V0 that one chooses, and the other important results automatically change. And the graph automatically looks good in all cases.

 

Problem: Solve for the overall efficiency of the ideal gas system as a function of n and m. n and m were defined in class and are also defined in the word document.

 

 

Interesting note: as of 5:08 PM on 10/22, I fixed the spreadsheet to calculate things for diatomic gas as opposed to monatomic. (When last seen in class, the spreadsheet assumed that the gas was monatomic, which is untrue.) Now the calculations are for diatomic, and things do change. Quiz yourself: which things change? If you look carefully, you'll notice the work does not change, so neither does the power. But what is affected and why?

Due Tuesday 10/16

 

Do this attachment.

Key to the Practice Test handed out in class on Friday 9/14

 

Also, attached is the original test form for those who were absent.

 

It's called Test 2017, because it's the test I gave last year.

Due Thursday, September 6: A very simple, but numerically specific thing

 

Research the Fluids at Rest section of Chapter 9 carefully enough to answer the following: "What is the atmospheric pressure difference between Heights A and B in the classroom if Height B is 10 cm higher than point A?" Write down the brief mathematical solution with a clear final answer with units.

 

You are to answer as an accurate number of Pascals. What you are doing is a careful reading of the Hydrostatic Equation (although your book doesn't call it that) so that you can apply it correctly. Any numbers you need to get this done are to be found in Chapter 9 itself when you access the proper paragraphs and/or charts or tables. You are talking about Earth's air as the fluid exerting the forces (and therefore pressures) on a 10 cm tall item. You are not talking about water as the fluid exerting the forces (and therefore pressures) on a 10 cm tall item.

An Example of how to make a good lab write-up