Physics 121 Frequently Asked Questions (FAQ): Fall 2017

Updated October 21, 2017

Most Urgent:

Question 1A. Does PHYS 121 Use the "Canvas" system?

Answer: We will make limited use of Canvas. Pre-lecture (video) homework will be delivered via Canvas. Also grades and the assignment calendar will be kept on Canvas. However, all regular documentation, including syllabus, course documents, homework, solutions, practice problems, etc. will be kept on the main PHYS 121 web page: 

Click on "Course Documents" to find the Syllabus, Course Information, Homework Guidelines, and Homework Assignment #01.

Question 1B. Where do I find .... ?


For PHYS 121, different critical materials can be accessed via two different hosts as follows:

  1. CWRU Canvas :

    We will make limited use of Canvas for PHYS 121. Here you will find:

  2. The PHYS 121 Web Page:

    This is the main page for the course and where you should look for most materials including:

Question 2A. Do I need to buy a textbook for the course?

Short answer: No, there is no required textbook that you need to buy. However, there are recommended textbooks. See Course Document #02, Section 4 for details.

Somewhat Longer Answer: (in response to several "But I don't understand" queries:)

The textbook by Ohanian and Markert is recommend, but NOT required. It's entirely up to you to decide if you want to buy it or not. You can get it new, used, e-book, whatever. We will not use the textbook as anything other that as a "supplement" to materials presented elsewhere in some combination of lectures, review sheets, videos and Online Notes. The Online Notes effective serve as the "required textbook" and they are free online. We will not assign problems from the recommended textbook. Readings assigned from the recommended textbook are optional.

Most students report that the recommended textbooks is not particularly helpful but some students find the textbook very helpful. It depends on your learning style. If you learn well from textbooks then try it out. Again: see Course Document #02, Section 4 for details. I've written two full pages of details about whether or not you should get the optional textbook.

Same for the i-clicker. Highly Recommended but optional. If you want to earn optinal bonus points, get an i-clicker and bring it to class.

Question 2B. Do I need to buy the latest version of the i-clicker? Do I need to buy the most recent edition of the recommended textbook?

Answer: You can get any version of the i-clicker, new or used, and it will work fine. You can use any edition of the recommended textbook -- or really any calculus-based textbook on introductory Newtonian mechanics you want. Whatever you find helpful in understanding the material and preparing to work problems is fair game. Again, we will not assign problems or required reading from the textbook in any case.

Question 3. Do I need to register for "The Expert TA"?

Short answer: Yes, you need to purchase a software license and register for The Expert TA so that you can complete the Online Homework for the course. The cost for a semester is $32.50. You cannot purchase the license at the CWRU bookstore (sorry) but instead you need a credit or debit card. See:

Question 4. Do I need to buy an "I-clicker" for PHYS 121?

Short answer: The i-clicker is not required, but it is strongly encouraged. You can get any version of the i-clicker, new or used, and it will work fine. With an i-clicker you can earn optional bonus points during lecture. See Course Document #02, Section 15 for details on optional bonus points.

Question 5. Are grades calculated on a curve?

Short answer: Yes, we "curve", at least we do if this helps students earn higher grades. We generally do not use a "straight" grading scale. In particular, for exams the line between an "A" and a "B" is usually in the mid-80s, and the line between a "B" and a "C" is usually in the high 60s to low 70s, percentage wise. This can vary from exam to exam. See Course Document #02, Section 14 for details.

Question 6. Suppose I have a question about something. I'm not sure where to look or how to ask. What do I do?

Short answer: Three options (consider these from first to last)

  1. The PHYS 121 Course Information and Policies (Course Document #02):
    This is 26 pages of detailed verbiage on just about anything you can imagine regarding the course. Look here for detailed information before asking your question.

  2. The PHYS 121 Phorum Discussion BBS:
    If your question is about homework, course content, or any topic that is about the course in general vs. something that is specific to your own personal situation, then I warmly encourage you to post your question on the PHYS 121 Phorum BBS. Good reasons to post on the BBS:

  3. Send E-mail to Corbin Covault (the instructor)
    Important points when sending email:

Question 7A. What is the policy regarding student absences from class, labs, and/or scheduled exams, homework, etc. due to sports or other extra curricular activities?

Answer: Okay first of all, students get worried about the idea that conflicts are going to be a problem. As instructor, I understand that students in the class have a diverse range of activities and interests and all of these are part-and-parcel of each students overall academic and personal growth during their time here at CWRU. So I understand and support students' activities and lives outside of the course, no worries at all.

Having said this, with so many students in the class, contending with dozens of special arrangements takes a great deal of time and effort. So anything you can do as a student to help smooth the process is much appreciated.

First, let me stress that it is important to recognize that it's really up to you, the student, and not your instructor and/or your coach or anyone else to take note of potential conflicts and make arrangements well in advance. In particular, getting a blanket note from your coach with all potential planned travel times doesn't free you, the student, from the specific obligation to make sure that ultimately your travel plans do not collide with important planned scheduled course activities. It's up to you -- and not your instructors -- to check all of the dates against the syllabus and your assigned lab times to see that none of your travel might potentially interfere with scheduled course activities including labs and exams.

For Physics 121 I tell students the following:

  • Question 7B1: What if I am ill and cannot take an exam?

    Answer: If you are feeling ill and you know that you may not feel well enough to take the exam please contact me immediately and directly by email ( to let me know as soon as possible that you might miss an exam. As a rule, you must do this before the time of the exam. If there is any doubt at all that you will make the exam, write me well before the exam. Students have an obligation and an onus to contact the instructor as early as possible before the exam. Much much better to contact us before the exam than after the exam. If this is you, send email now. Do not delay: Send email as follows:

    Please sendthe subject header: "PHYS 121: Too ill to take exam on [date]" . Send email directly to We will try to respond and make arrangements for an alternate exam to be taken at a later date when you are feeling well. Depending on the situation and/or nature of the conflict and/or illness we may need further follow up and/or confirmation of your illness. Especially if you are ill for more than one or two days, you will almost certainly want to coordinate your request for make-up work with your academic advisors and/or the dean in the Office of Undergraduate Studies. Note that the Office of Undergraduate Studies can help you document your illness and can help you to coordinate communiation between yourself and all of your faculty instructors.

  • Question 7B2: What if I miss and exam because I accident overslept or forgot and/or something disruptive and/or unplanned might or did happen?

    What about missing an exam for reasons besides illness?

  • Question 7C. What if I am ill and cannot a homework assignment? What if I have a personal conflict that collides with a homework due date?

    For students who have a minor illness and/or personal conflict that impacts their ability to complete one or more components of the homework, I will usually remind students of the "we drop your lowest homework score" policy. In other words, we already "bake in" the idea that once a semester, an illness or a personal disruption might result in a missing or uncharacteristically low homework score. Because of our policy of throwing away the lowest score, this will not hurt your grade.

    If your illness or personal situation has the potential to disrupt more than one homework, you can email me to request an excuse from the specific homework well before the due date. I don't usually give out such excuses unless your situation might impact your work over an extended period of time -- usually at least a week or so. Important: In the case that you have a medical condition or other circumstance that has the potential to impact your work over a period of more than a few days, I would strongly recommend that you also contact your advisor in the Office of Undegraduate Studies (dean's office). This office can help you make arrangements to document your condition and relay requests for temporary accommodation to all of your course instructors and/or can refer you to ESS if you need extended accommodation.

    Important note: An excuse is not an extension . If you are excused from an assignment, we will not include the excused assignment score for that assignment into your "homework average" when we calculate your semester grade. Instead, we will use your other submitted homeworks to synthesize a score for the excused homework. When we excuse a homework assignment, we generally will not accept it late to be graded. However, we will generally require students to submit the excused work (later) and we may (or may not) "grade only for feedback only" (depending on how late the work is submitted). Such grades are for student information only and will not be incorporated into semester grades. Note that in general, replacement scores for excused assignments are calculated at the end of the semester. Important: Give any "excused" homework assignments directly to my hands (Corbin Covault) OR put it under the door of my office, Rockefeller 207 if I am not available. Please write in large clear letters at the top: "Submition of EXCUSED Homework" and mark the date of the email that I gave you an excuse. Do not submit "excused" homework to the homework box. It will get lost.

  • Question 7D. What if I am ill and cannot attend lab and/or my illness disrupts my ability to complete lab assignments? See the notes on policy of the labs at:

  • Question 7E. What can I do if I messed up when I submitted my pre-video quiz and/or my online (Expert TA) homework?

    Short Answer The way we do grading, if you make a mistake in the submittal of your electronic assignments, the system is quite forgiving in terms of the impact on your grade. See also this post on the Phorum Discussion.

    Note also that for both Pre-Lecture video assignments and for Online Homework, assigments are (sometimes) accepted a little late. It sort of depends on the system. Assignments submitted may be marked down and/or may receive zero credit depending on how late the submission and/or how often subissions are late. Note that for the written homework, no late assignments are accepted.

  • Question 7F. I submitted my Online Homework via The Expert TA, but I do not see a corresponding score for the work listed on Canvas. Is this a problem?

    Short Answer No, it's not a problem. There is no mechanism for automatically transferring scores from The Expert TA server to Canvas. This has to be done manually, and we are planning to do this perhaps once every two weeks over the course of the semester. Rest assured that all scores recorded at The Expert TA will (eventually) be transferred into your Canvas record.

  • Question 8. I joined the class late, and as a result I am not sure what I need to do to catch up and/or I may miss and/or I have already missed deadlines for submitting one (or more) assignments (for example, the first pre-video homework and/or the first online homework and/or the first written homework). What can I do?

    Answer: We have students join the class late all of the time. A few points:

  • Question 9. Thanksgiving: Will there be a lecture on Wednesday, November 22, the day before Thanksgiving?

    Answer: In accordance with the University Academic Calendar, there will, indeed be a lecture. But based on past experience, many students will be under some pressure to depart campus early for family events. Therefore, the material covered in this particular lecture will not be of "central importance" to the course. Yes, we will talk about physics, but it will be a "fun" lecture, with some amusing surprises, and maybe a treat at the end. If you are stuck on campus for the holiday, I urge you to come to class, I think you will enjoy it. If you need to miss it, you can always catch the fun on the Mediavision video, (although perhaps you will not be able to partake in the "treat").

    Question 10: I have a Problem with my Homework. My Homwork is Missing or the score is Wrong or I need to fix my homework score and/or I am worried that the correct scores will not be included in the final calculation of my grade and/or I am worried about getting this dealt with soon. What do I do to add or fix a missing homework score? What is the deadline for getting the grades fixed?

    Answer: First: Don't worry. Don't be anxious. There is no deadline. Please be patient. More specifically, I am completely committed to ensuring that every student gets all of the correct homework points that they deserve. This means that there is no deadline for resolving these issues. It also means that peppering Mr. Covault with anxious emails about how one of your homework scores is still missing will not help and is completely unecessary. When I say no deadline, I mean that even after letter grades have been reported to the registar, if we find a mistake or an omission on the homework score and it impacts your grade, we will change your grade.

    The following procedures below are specifically designed to help us make the corrections to your homework grades as easily as possible. Making many corrections takes alot of time and work so it is very important that students follow the procedure exactly as indicated below.

    Question 10A: My submitted Written Homework should have been graded, and returned to me, but it is missing. What do I do?

    Answer: Ideally, each student will have each homework graded and returned to them in a timely manner (in about a week) with the correct score recorded on Canvas. Here's what to do if this doesn't quite happen: Important: please follow this procedure exactly to enscure that your grade will be fixed.

    Question 10B: I have a written homework that has been graded and returned to me, but the score on Canvas is either missing or incorrect. What do I do?

    Answer: Ideally, each grader will enter the correct score into Canvas for each graded homework. Here's what to do if this doesn't quite happen:

    Question 10C: The homework grader made a mistake and/or missed some of my work on a particular homework resulting in a lower score than I should have received. What can I do?

    Answer: As a rule, we do not support re-grades on homework in Physics 121. Sorry, this is just too much work. In comparison to the exams, the homework grades count much less, and haggling over a tenth of a point or so on the homework (out of 1000 points in the course) is very unlikely to impact your final grade. Remember that homework is meant to be a formative assesment and not an evaluative assesment. In other words the whole point of homework is to help you learn the material and not to determine how much you know or the quality of your work. Our policy of randomly assigning homework graders and throwing out the lowest homework score, and awarding bonus points for practice problems also tend to mitigate against any potential negative impact of small grader errors on homework. So as a rule, no sorry, students cannot ask for a re-grade on the homework There is really only one exception to this rule and that would be in the case that the grader made a "gross error" -- like completely missing a problem or two -- that resulted in an error of "several points" taken off that should have been awarded. In this (rare) case, please come see me during office hours as we can take a quick look. But, no, if you are looking for an extra point or two on the homework, because the grader made a careless mistake, we just don't do this because it is too much time and too little impact, sorry.

    Question 10D: My grade is wrong on one of my exams. What do I do?

    Answer: We want all students to have the correct score corresponding to what they earned on any given exam. In particular:
    1. Students should follow the procedure outlined in Course Document #16 to request a re-grade if you feel that the grader has not correctly awarded the right point value for any reason.
    2. Students should follow the instructions in Course Document #16. Students should not come to ask about potential re-grades during office hours.
    3. The procedure is the same for any correction that needs to be made on any exam. This includes point tabulation and point tally errors. Following the procedure in Document #16 will ensure that the corrected score is put into your record.
    4. Again there is no deadline to request an exam regrade.

    Question 10E: How is my mid-term grade calculated? What if something is wrong with my mid-term grade? How can I get this fixed?

    Answer: See the following web page regarding how the mid-term grades are calculated:
  • If your scores on Canvass need to be corrected, follow the proceedures listed for Question 10 above.
  • If you have the correct scores and your calculate a different letter grade than you see posted to SIS, please send email to me in the following example format:
         From: Jane Student 
         Subject: Physics 121  Canvas Midterm Letter Grade Cross-check
          Dear Mr. Covault:
          My name is Jane Student and I am in your Physics 121 class.  My
          Case NetID is jxx934.  When I look at SIS I see that I have been
          assigned a letter grade of "C".  However, when I calculate my
          expected midterm letter grade based on the method described in
          mtcalc.html I get a total score of 76.5 out of 100 which should
          correspond to a "B".  Can you please cross check to see what
          the correct mid-term letter grade should be?  Thanks very much. 

    Question 10F: How do Clickers earn Bonus Points? How does this work? What do I have to do to earn these? How can I check how many clicker points I have?

    Answer: As described in Course Document #02, students who register their Clickers can be awarded optional bonus points during the semester. As long as you register your clicker before the end the the semester, you are eligible for all bonus points earned for each time you participate during lecture for the whole semester. Bonus points are awarded based on participation, not correct answers. When clickers are used in a given lecture, there are usually one or two bonus points awarded to those student who participate. The maximum number of optional bonus points earned for the whole semester will be between 30 and 40 points per student, to be determined. There is no mechanism for students to determine a tally of the number of bonus points awarded. Most students who attend lecture regularly and bring their clickers can expect to be awarded most of the bonus points.

    Note that clicker points can only be applied on the Final Exam and they can only be applied on exactly one of the nine exam problems. In essence, clicker bonus points can act as a little "extra insurance" against getting a particularly low score on a single exam problem. Each exam problem is worth between 30 and 50 points (the final exam is worth a total of 350 points). Bonus points can increase the score on one problem up to the maximum score for that one problem. Bonus points will automatically be applied to the one problem that maximizes the total score. Student requests to apply bonus points to any particular problem will be ignored.

    Note that bonus points can be awarded but they are never earned. Participation with clickers and clicker bonus points is completely optional and the awarding of bonus points is completely at the discretion of the instructor. Students must never "count" on bonus points when calculating or estimating their exam and/or letter grades for the semester. There is no appeal process regarding the award of bonus points, and requests for calculating, correcting, or otherwise fixing bonus point awards will be ignored. Important: The entire bonus point program can be canceled and/or all student bonus point awards can be zeroed-out and/or deleted by the instructor at any time without warning, reason, or justification. Clicker points are a "gift" that you may -- or may not -- end up receiving in the end.

    Question 11: Things are not going so well for me this semester in Physics 121. What can I do to improve?

    Answer: Every student's situation is different, and there is no such thing as a "one size fits all" best approach to the material. Having said this, many students find themselves struggling in electromagnetism at the midterms. So here are a few observations that may apply:
    1. The course is deliberately front-loaded. This means in terms of new materials, we have already covered more in the first half of the class than we will in the second half. We will cycle and we will review. This gives everyone in the course another chance to improve and master concepts that have may not have been understood the first time around. So even if you are feeling behind, it's not too late to get on top of the main points of the class before the final exam.

    2. I find that for many students, it's the concepts that are challenging, not the technical issues. These concepts are identified by special words and incorporated into physical laws. What exactly do we mean by the word "flux" for example? What does Gauss' Law actually tell us? What exactly do we mean by the term "voltage" anyway? Mastering physics means understanding these concepts. If you are able to improve your understanding of the concepts, you will improve your grade in the course.

    3. I can't emphasize enough that even if you are doing poorly so far in the class, you have lots of time to improve your grade. The final exam is worth 35 percent and a strong performance on the Final can really improve students grade.

    4. Have a look at the materials published on the main web site under the heading "How to Earn an "A" In Physics 121" Much of these advice is helpful for a student at any level.

    5. In particular, plan to take advantage of office hours. During office hours I will generally ask to inspect your exams and I may ask you some questions about how you are going about tackling the problems. This allows me to diagnose to some degree where you are at with the material and this in turn usually suggests some specific study strategies that you might use to improve.

    Question 12: Things are not going so well. I am thinking of dropping the course. Should I drop the course?

    Answer: The answer is almost always the same: Do Not Drop the Course!. Students are very often doing better than they think. Very few students who stick it out to the very end fail the course. And if you are going to earn a passing grade, usually it is much better to get through withot having to re-take the whole course -- a very time-consuming and expensive propasition.

    Let me ask you to at least do this Before you make an irrevocable decision to drop the course, consult directly with the instructor, (me) Corbin Covault by email. Please consult with me before deciding to either drop the course and/or to take the course P/F. Usually students who decide to drop the course and/or who decide to switch to P/F regret their decision. Better you should consult with the instructor before you make any such decisions.