How to Pass Physics 212

Transcription

1 How to Pass Physics 212 Physics is hard. It requires the development of good problem solving skills. It requires the use of math, which is also often difficult. Its major tenets are sometimes at odds with every-day (deeply held) beliefs about how the world works (e.g. a body in motion tends to stay in motion, which, because of friction, is at odds with our everyday experience). Unfortunately, for many students this objective fact often translates to the subjective I can t do physics. Like Physics 211, on average, just under 10% of students drop Physics 212 before the end of the semester, and of those students who remain, about 15% receive either D s or F s in the class. Although these numbers aren t out of line with other introductory science classes, they are sad, representing hundreds of wasted student semesters. Importantly, it doesn t need to be this way. The idea that students who don t pass physics can t do physics is nonsense, as is demonstrated time and again by students who have failed in the past then come back to do very well the next time through. We are revamping the introductory physics sequence to improve student learning and, in part, to try to help those who, in the past, wouldn t have succeeded. For those students who are motivated to work hard and do well, these changes should be particularly helpful. However, we acknowledge that for many students physics is viewed as an obstacle that must be moved around, ideally with minimal effort, in order to get to classes they really care about in their major. Although we think this is an unfortunate view and hope to convince you during the course that physics is not only interesting and useful, but also fun, if your feeling about physics mirrors the above then this guide is for you (if you want to do more than pass the class, check out our companion guide How to Do Well in Physics 212 ). Guide Objectives In this guide we will give you a course of action for passing (C or better) Physics 212 with minimal effort. Note that this doesn t mean no effort of course to pass a hard class you will need to do some work. But if you need to pass the class for your major, for example, then not doing the work and not passing is just a waste of time. Although we can t say that following this course of action will guarantee a passing grade, we know from many years of collective experience what common pitfalls lead to failure, and we here tell you how to avoid them. If you don t want to read the details skip to the summary at the end. Course Requirements To earn a C you need an overall grade of >70%. Here is what makes up your grade in physics 212: In Class Recitations Laboratories Learning Exercises Concept Quizzes Midterms Final ,15,15 25 These assignments can be broken into 3 categories: classwork, homework & exams. How to Pass Physics 212 Page 1

2 Classwork 21% of your grade comes from classwork (recitations, labs & clickers in the main class). These should be viewed as almost free points. If you bring your clicker to every class and use it, you will earn the full 3 points. For students who attend recitations and labs, the average score is 95% (it is impossible, if you participate, to earn less than 75%). Participating in class activities is the easiest way to earn points do NOT miss class. Though the average lab and recitation grades of students passing 211 last fall was 92%, the grade for those failing was 60%. That difference is almost entirely attributable to the skipping of class by students who ended up failing the course. It lost them about 6% (3/4 a letter grade) on average. Of course, the reason that we assign points to these activities is because we know that by participating in them that you will learn the material (recently, students who attended lecture always outscored students who attended rarely by nearly 50% on the final exam). Don t just attend classes, participate in classes. If you are spending time there anyway, you may as well take full advantage of your time. To do so, that is, to effectively participate, you must come to class prepared. Thus our next section: read the textbook. Read the Textbook Reading the textbook (Knight, Physics for Scientists and Engineers, 3 rd edition) BEFORE CLASS is probably the most underrated yet time effective way of making sure you pass physics. Students in a recent class who read the text most of the time outscored their peers who rarely read by more than a full letter grade. Most students won t walk into a literature class without having read the book, but feel no qualms about doing so in a science class. Partly this is the fault of many textbooks they are dense with equations and hard to read. Knight is quite readable and provides many physical insights and problem solving tips in the text. We encourage you to read by asking questions about the reading before class, and by beginning each class with a quiz about the reading (which makes up half the In-Class 3% score). We don t expect you to completely understand everything before coming to class. But an hour spent reading the text and thinking about what you understand and what you don t will make the class significantly more helpful to you, not to mention enable you to do Mastering Physics. Mastering Physics The online homework system, Mastering Physics, is designed to help you learn the material. Although the average grade on homework does scale with course grade (last semester: 98% for A students, 85% for C students, 40% for failing students), again, most of this is due to students skipping problems or entire assignments. That is, students who actually attempted the problems typically got nearly full credit for them. There are two reasons for this. First of all, we deduct minimal points for incorrect answers, so that you can try multiple times to get the right answer. Secondly, a lot of people cheat, either by copying from friends or by finding answers online. How to Pass Physics 212 Page 2

3 This latter method, though leading to a good homework grade, is not only forbidden by Penn State policy, but also highly destructive to overall course performance. In a study from a few years ago, students who copied more than half their homework assignments failed at rates 20 times higher(!) than students who didn t copy, even though coming into the class both group of students did equally well on a pre-test. In a recent class here, students who self-reported copying more than half the homework scored on average half the final exam score of students who reported never copying. DO NOT COPY (from friends or the internet). How should you do homework effectively (in the least amount of time, with the most success, without cheating)? First of all, make sure that you have read the textbook before beginning the assignment (this is much more time effective than trying to flip back into the book looking for similar problems to solve the one at hand). Secondly, MP provides hints for many of the problems. Read these (there is no penalty for using them). They will walk you through the process of solving the problem. Finally, don t do homework alone. At least, don t spend more than just enough time to read the problem and the hints and think about them (generally 5 minutes per problem, or about an hour per assignment). Some students report spending hours banging their heads against a problem. This is both a waste of time and counterproductive it frustrates you and makes you think you can t do physics. The most time effective way to do homework is to do it with other people (discussing and thinking together, not copying!), often most effectively in office hours. Use Office Hours This is by far the least used resource in the class. Though more than 1000 students are enrolled in our classes each semester, the average graduate student instructor reports that only one or two students come to their office hours, if any. That means there are essentially 2 dozen private tutors waiting for you to visit them each week. In two hours of office hours you should easily be able to finish any homework assignment, making sure that you not only get credit for the assignment, but also that you have talked through the difficult aspects of those problems, some of which will appear on your exams. I have heard students say that they don t go to office hours because it is somehow an admission of failure. This couldn t be further from the truth typically it is the best students who come, because they know that it is a good way to learn the material. There is no shame in asking for help. What is shameful is not asking for help when you need it and instead failing the class. Other students say that they are so lost that they wouldn t know what to ask. If you are in this situation you should definitely go to office hours. It is fine to say exactly that to an instructor: I am lost, can you please help me figure out what I should know and how to go about learning that? Furthermore, if there happen to be other students at the office hours, just listening to their questions can be very helpful in understanding how to think about problem solving. How to Pass Physics 212 Page 3

4 Exams The bulk of your grade (70%) comes from tests. Our introductory physics courses have a policy that if the mean on exams is below 70% we will add whatever is necessary to everyone s score to bring the mean up to 70%. Often, about half the class will have scores below 70%. At first glance it might seem that we are setting out to fail half the class (since a 70% class grade is what you need for a C). However, if you have done average for the non-exam parts of the course (95% classwork, 90% homework) you will have already earned 28%, thus only needing about a 60% average on the exams for the C. Earning a 60% average on exams is, however, NOT trivial and will require work on your part. Even if you were an A student in high school physics we guarantee these tests will be challenging. First of all, it is important to understand how physics exams work. A typical midterm has 20 multiple choice questions on it (the final has 25). Continuing and effort started last semester, we are significantly extending the time for midterms, in an effort to remove (or at least reduce) time as a factor in your exam performance. Why? Because we want to test your understanding of concepts and of your problem solving abilities, not of your speed. When we write questions we think about the common mistakes that students make and the typical confusion between similar but different problems, and make sure that distractors (wrong answers) consistent with these mistakes are offered. Again, we do this because we want to make sure that you really have learned the material. Thus, in order to pass these tests you really do need to actually learn some material. Memorizing formulae or past exam solutions will not help the questions are a test of understanding, not memory. We provide a number of resources to help you pass, however. First of all, for each exam we will provide at least two sample exams, often three. We carefully write these exams to cover the same material with very similar difficulty. Note that our exams will be quite different in nature from previous semesters, so although you are welcome to use previous exams as a resource, they probably won t be particularly time effective in guiding your study (and, very definitely, memorizing the answers to previously asked problems in the hope that they will again appear is a complete waste of time). We suggest that after a fairly brief review, the weekend before the exam, you should take a sample exam. Take it under exam conditions (closed notes, timer on your desk, no music, no electronics, no talking roommate ) After you have written down your answers, put away the questions (do NOT look to see which problems you missed). Instead, in the answer key we indicate which concepts each problem covers. Determine which concepts you are weakest on and study them. We will have a number of sample problems in Mastering Physics, organized by topic. But you should also feel free to go to an instructor s office hours and say I seem to have difficulties with these kinds of problems, can you please help me learn how to do them? We are here to help you learn! After you have become more confident in the topics you had difficulties with on the first sample exam, take it again. It will still be an effective test because you have not looked to see which problems you got or missed. Repeat this process until you get to your desired score, then take the 2 nd sample exam (and 3 rd ) to make sure your score is consistently high enough. Then stop. Yes, with more study you could do better. But if your goal is to pass the class with minimal effort, that s all you need. How to Pass Physics 212 Page 4

5 Group Work A final note about taking full advantage of your time. In recitations and labs you will be working in a group of 3 students (assigned at the beginning of the semester and fixed through the course). The goal of working in a group (aside from the generic but true idea that almost all work in the real world is done in groups, so we want to help you learn how to effectively work in groups) is that if you don t know how to do something you can ask your group mates. Some students are very reluctant to do this. They don t want to slow down the group by asking stupid questions. They don t want to show their group mates what they don t know and they don t want to bother them. Although we can t promise that one or both of your group mates won t be ridiculously uptight and upset about you asking them questions, we can assure you that they shouldn t be. Taking time to talk through recitation and lab work to the point that ALL group members understand what is going on is helpful to all group members. Teaching others is one of the most effective ways to really learn the material by asking your group mates to explain a concept to you, you are helping them rethink their own understanding of the material and making them understand it better. From many years of experience observing group dynamics (as well as education research on group work), we know that students in groups which encourage questioning and discussion end up learning the material better and doing better in the class both the students doing the asking and those doing the answering. Of course, there will be some limits to your group mates good will. If you go to recitation not having read the book, not having attended the classes leading up to the recitation and not having worked through the mastering physics assignments which set up the materials being discussed, then you will very quickly wear out your welcome. Summary: How to Pass Physics 212 Here is a summary of the main points we ve discussed: 1) Read the textbook before doing the MP and going to class (~1 hour per class) 2) Attend (and participate in) class, recitation & lab (working WITH your group mates) 3) DO (don t copy) the MasteringPhysics (~2 hours per assignment, use office hours!) 4) Study for exams, making sure you get the score on the sample exams that you want on the exam If you faithfully follow these steps you will find it hard not to pass physics 212. Again, if your goal is to do more than pass, check out our guide How to Do Well in Physics 212. Feedback Please Finally, we would really appreciate any feedback you could give us to improve this guide for future generations. Something work for you that we missed? Something unclear? Feel free to your comments to [email protected] How to Pass Physics 212 Page 5