Physics 240 Assignments - Fall, 2009 - Dr. Cohen
Show your work or reasoning for all problems!

Due Assignment Comments
Mon 8/27 The following instructions pertain only to students already registered for Physics 240 at Grossmont College.  Registering with WileyPlus does not give you permission to take the class.  It is something you do after you have enrolled in the class at Grossmont College!

The first thing you need to do is to register for the course with WileyPlus.  You do that by going to the site http://edugen.wiley.com/edugen/class/cls125975/ which is specific to Physics 240, not to sections of Physics 140.  If you cannot easily figure out what to do, you can go to www.wileyplus.com and look at the materials labeled as:

Need Help Registering? View a 2-Minute Tutorial now.

Visit the students' 1st Day of Class website for tutorials, user guides, & more.

Assignments will be listed on the date due, not on the date assigned! Other announcements will be listed as they occur.
We will be covering the first two chapters of the semester merged together.  The order will be approximately as follows:

18-1 → 18-8 (with the constant volume gas thermometer and 18-6 in lab)
18-12 (conduction only)
19-1→ 19-5 (skipping 19-6 & 19-7)
18-9→ 18-11 (work done by an ideal gas in the second part of 19-3 will be covered here)
19-8→ 19-11
Thu. 8/27 Calorimetry lab.  For the next three labs, we will be using open flames.  If you have long hair, bring a hat or use some other way to keep your hair out of the flames.  Wear closed toe shoes!

Bring your lab notebook to record your data. 

Be there at 8 A.M.

I find the following website useful for constants:

http://hyperphysics.phy-astr.gsu.edu/hbase/tables/ttab.html

 
Thu. 9/3 Thermal Expansion lab.  You will need your lab notebook to take data.  If you have long hair, bring a hair-tie or hat!  BE ON TIME! Calorimetry lab due here, during the lab!
Sun. 9/6

The first homework assignment is assigned and is due on this date!

When you go to the course website, you will find an assignment.  All these problems are to be done online.   They do not all have the same format; some are numerical, while others are multiple choice.   I recommend printing them out and thinking/working them out offline.  Only when you have finished working them out on paper should you enter the answers. 

Homework comments:

1) Most of the homework problems ask for a specific number of significant figures.  I have found that you get the answer closest to the book's answer if you do NOT round off intermediate steps to the correct number of sig. figs.  Only round off the final answer.

2) You can enter numbers in scientific notation if you need to do so to get the sig. figs. in correctly. An acceptable format is #.##e# (e.g. 1.23e4)

3) The book is not sticking to just one set of units here. They are using cal and Cal (what's the difference?) and putting specific heat in terms of J, kJ, g, and kg.  Be careful.

4) I don't think the answers are completely consistent on where to use Cº instead of ºC.  So, don't wait until the last try to enter your units!
Mon. 9/7 Labor day, no class.
Thu. 9/10 Because of the short week, we will have a lecture instead of a lab.  The lecture will not last for 3 hours!  Time to start will be determined by class vote the day before.

Starting time: 9:15 A.M.

 Because of the holiday on Monday, you won't get your calorimetry lab back in time to incorporate any "suggestions" from my comments. So, the Thermal Expansion lab is NOT due here.
Sun.9/13 The second homework assignment is assigned and due here. Starting with this assignment, late problems will be given half credit!
If you are having trouble with the website (not with physics!) try looking here: http://hesupport.wiley.com/wileyplus  If you can't find help, you can contact Wiley tech support there as well.
Ed, our tutor from last year, will be available in the computer room starting Monday, 9/14.  See the board in that room for times.
Thu 9/17 Determination of absolute zero.  As always, you will need your lab notebook to take data.   Bring a hat or hair-tie or hat if you have long hair!  Wear closed toed shoes! Thermal Expansion lab due here.
Sun.9/20 The third homework is assigned and is due here.  When you are doing this homework, remember that on the test I usually assign a problem based on a cyclic problem of three steps, including, isobaric, constant volume, and adiabatic or isothermal stages.  This could involve calculations of T, V, and P at different points; the change in internal energy, work, and heat for each stage; and the efficiency. 
Mon.9/21 We should  finish entropy today.  We will start electricity and magnetism whenever we finish entropy.
Thu 9/24 This is a short lab, so we should have time for a quiz.  The quiz will be on gas laws and the first law of thermodynamics. You will have to calculate internal energy changes, heat, and work for one or more of the four processes we have used: constant volume, isobaric, isothermal, and adiabatic.  The quiz will start promptly at 8 A.M.  If you are late, you will not have the full time.  If you miss it, there are no makeups.  I will give you the thermodynamics formula sheet shown on the main web page. Boyle's law lab.  Bring your lab notebook!
Absolute zero lab due.
Sun. 9/27 The fourth homework assignment will be due here.
Mon.
9/28		 Review for exam will take place in Monday's class.  The problems are posted here. There are only three problems, but they have multiple parts, so they give pretty good coverage of what you need. 

 The solutions are now posted in WileyPlus. 

Homework solutions are also now posted in WileyPlus.   In the future, they will be posted after each homework assignment is due.
Thu. 10/1 Test on chapters 18, 19, and 20. Bring a non-programmable scientific calculator.  You can turn in the Boyle's law lab if you want to, but it is not necessary to turn it in until next week.
Here is the formula sheet from an earlier semester.  It may have additions or corrections added. 
Thu. 10/8 The fifth homework is  assigned and due here.  Since some of you probably won't start it until after the test, this gives you a week to do it.  However, the next assignment may come upon you before you know it!
Simple Ohm's law lab.  The exercise will be handed out in the lab.  You do not need your lab notebook. Boyle's law lab due.  Some of you still need to go back and look at the guidelines.  For example, in the most recently submitted lab, there were still labs with incorrect summary tables.  Also, you need to read the instructions in the lab itself.  Graphs must be big - not tiny!  Remember that all data must be converted to either Pa and m^3 or atm and L.
Mon. 10/12 The sixth homework is assigned and due here.  This is a shorter than usual assignment on electric fields from point charges.
Thu. 10/15 Van de Graaff generator lab.  Make sure you show up at the start!
Mon. 10/19 The seventh homework is assigned and due here.
Thu. 10/22 Electric Fields and Potentials lab. The Van de Graaff lab could be due here, but you don't have to turn it in until next week. 
Mon 10/26 The eighth  homework assignment is assigned and due here. 
Thu. 10/29 Written homework problems have been posted and are due here!  They should be written up the old fashioned way.  Here they are. These can be turned in for credit Monday by the end of class. 
Capacitor lab.  We will measure the capacitance of some notebook paper and also the textbook pages.  Bring your textbook to class.  You should turn in the Van de Graaff Lab here, if you haven't already. 
Mon 11/2 The 9th homework assignment is assigned and is due here. The written homework can be still be turned in for credit, as long as you turn it in before the end of class.
Mon.11/2 Review for the test.   Here are the review problems.  Make sure you read the introductory paragraph  of the review problems for more information about the test. Several of the review problems are harder than any test problem will be.    A scanned version of the handwritten answers will is posted inside of WileyPlus.
Here is the Formula  sheet from last semester.
Thu. 11/5 Test.  Chapters 21, 22, 23, and 24.  This covers fields and potential of point and distributed charges. Gauss's law.

Here are some problems that will certainly be on the test: (not necessarily in this order):
1) electric field and potential of two point sources (NOT on the axis of a dipole).
2) electric field inside and outside a charged insulating sphere or long cylinder.  This will have a non-uniform (but symmetric) charge distribution.
3) motion of a charged particle in an electric field ("projectile" type motion).

I may add more later; check back.
Fields and Potentials lab due at the START of the test.  Remember, you don't have to do a full writeup.  Draw the equipotential lines based on the measurements and sketch in the field lines.  Do this for each drawing made by your group, your own and copies of the other ones.  YOU NEED THREE!  Then use the equipotential lines to calculate field strengths on one of the drawings as described in the writeup (use the best one you have!) and answer the questions.  This is good practice for part of the test!  Make sure to use the Electrostatics program to model your chosen drawing.
Thu 11/12 The 10th homework assignment is posted and is due here.   (Note: the rest of the homeworks may not have the standard Sunday due dates.)
Wheatstone Bridge Lab. The capacitor lab is due.  Remember that there are two separate sections.  You do not calculate or use the dielectric constant in the first part!

In order to work with magnetic fields, you need to know how to calculate the vector cross product using components in 3 dimensions.  If you don't remember how to do this, you can find the math in chapter 3 of Halliday, Resnick, and Walker.   You can also find it in chapter 10 of Tipler and Mosca.  There is a copy on reserve in the library.  While you're at it, review torques in three dimensions (hint: electric motors).  Also, go way back and review circular motion and centripetal acceleration (charged particles move in circles or spirals in a magnetic field.)
Thu. 11/19 Torques on a current loop lab.  This lab will not be due for a long time! Wheatstone Bridge lab due (but you can turn it in on Monday without penalty.)
Sun.. 11/22 The 11th homework assignment is posted and is due here. 
Wed.11/25 We will probably do a lab during the class period.
Thu. 11/26 Holiday, no class!
Mon. 5/4 The 11th homework assignment is posted and is due here. This is postponed to May 6..
Thu. 5/7 Charge to mass ratio of the electron lab. Torques on a current loop lab due.
Makeup test. You may choose to redo 10 points worth of problems (not including 1 - 5  which cannot be made up) and have the difference in your score for those problems added to your grade.  The problems on the makeup will either be identical to the problems on the test or on similar material.   If you choose to take advantage of this option, you must hand your old test back when you begin taking the makeup.  If you don't save your old test, you cannot do the makeup. You must clearly mark the problem (s) to be redone on the front of the makeup.  The answers must be perfect or near-perfect to receive credit.  Makeup problems with significant errors will receive no credit. You can have about 30 minutes for the makeup problems after everyone is done with the lab.

You can make up one 10 point problem , or two 5 point problems.  For the purposes of this makeup, the first 10 point problem (problem 6) can be considered two separate 5 point problems. 

Mon. 5/11 There should be homework due here, but I made it due after the test.  That means that there will be two homework assignments due fairly close together..
Thu. 5/14 Test: chapters 25, 26, 27, and 28 .  Here are some review problems.   There will be no in-class review session.  The scanned answers have been placed in WileyPlus.

Here is the formula sheet.  Look it over for mistakes or (what you think are) omissions.  You should look it over before the test as some formulae are given in condensed form, and you should make sure you know what all the symbols mean.  For example, the charge on a capacitor in an RC circuit is given as a function of time.  How would you derive the current and voltage as functions of time?  I will also add the first page of the Physics 140 formula sheet that is shown here.

The test will include a number of problems.  Problems worth 5 or more points will probably be as follows, but there could always be a problem on anything we covered:

1) a charged particle moving in a magnetic field: force and path
2) force on a current carrying wire made of one or more straight line segments in a magnetic field.
3) capacitors in series and/or parallel
4) a network of multiple resistors in series and parallel with one battery
5) a network of multiple resistors with two or more batteries (Kirchoff's node and loop rules required).
6) torque on a current loop

Other problems which could be worth lesser numbers of points could be as follows:
1) resistivity and resistance
2) charging or discharging an RC circuit.

Short answer problems could be on any topic.

Again, check back to see if there are changes.
Sun. 5/17 The 12th homework assignment is assigned and is due on this date.  This is on chapter 29.
Thu.  5/21

Last day of class.

"Charge-to-mass Ratio" lab report due. 

Oscilloscope lab.  LC and RC circuit time constants.  There will be no writeup to turn in.
Mon. 5/25

The13th homework is assigned and due on this date.  This is on chapter 30.
We will cover portions of Chapter 31 for the final.  We will cover portions of sections 6, 8, 10, and 11.  We will not even cover all of the material in these sections, but only what we go over in class.  For example, we will not cover phasors. 

The 14th (optional) homework assignment is assigned and "due" on this date.  The points for this assignment will be treated the same as for all other assignments, except they will only go in the numerator, not the denominator, when the homework percentage is computed.  Although the homework is optional, the material will be covered on the final. 

I do not currently plan to have office hours finals week.  However, you can send me questions by email, and I will try to answer them.  Also, you can always call my office on the chance that I am in, but most likely I will be at home grading the labs! 
Thu. 5/28 The final will be Thursday, May 28 from 8 - 11 A.M.  You must contact me in advance if you would prefer the final at the official time of 7:30 - 9:30 A.M.
The final will cover chapters 29, 30, and part of 31.  Remember, although the final concentrates on material from those chapters, you may be expected to use knowledge from prior chapters (or semesters!) during the test.     Physics is cumulative.  I may post more information about what will be on the final after I think more about the material we have covered.
Labs can be turned in at the final.  The "charge to mass of the electron" can be turned in with the same deductions we have been using for late labs throughout the semester (-1 if I haven't graded them; one point per day up to half off if I have graded them.)  Any other lab which has not been graded by the final will receive the same treatment.  Labs which have been graded (other than the e/m lab), regardless of whether they have been returned, will receive three points for having taken the data, regardless of how much or how little of the writeup you have done.  Note: I plan to have all labs graded by the final, so the heavier penalties will probably apply to all labs not turned in to me or in the physics department mailbox by the time I go home on Thursday, May 21, at 3:30 P.M.  If you want to, you can put labs in my mailbox after that, but there is no guarantee I will find them in time.

At some point  I will post the last possible time to do homework for credit.
Here are some review problems.  Written solutions have been posted as a document in WileyPlus.    Remember that these are primarily reminders of the topics we have covered.  Do not expect a one-to-one correspondence between review problems and test problems.
Here is the formula sheet for the test.  Look it over to make sure you understand what each equation refers to.  You may also email me suggestions on additions or corrections, although I don't want to change it unless there is something really important.  If any of the problems on the final look like they might need the Physics 140 formula sheet, I will include that.
A cumulative grade has been posted with the three tests, the makeup, and all graded labs.  The homework included is that which was done by test 2.  As labs are graded, they will be added to the total and the grade automatically adjusted.  The homework score will not be adjusted until after the final.
Tue. 6/2

The test is graded and posted, along with all scores except for a few late labs and the homework.  Remember that the homework was only extracted up through test two.  So, if you did homework up until then and then stopped, your homework percentage will go DOWN!

Homework now closed.

The homework scores will be extracted from WileyPlus at 5 P.M. P.D.T. on Tuesday.  No late homework after that will be counted.  Don't go back and work on problems where you already have half the points, or you will wind up with less.  That's the way it is recorded for the instructor!  Most of you have done all the assignments, but there are a few of you who have one or two that you haven't done.