STEP 3 Develop Strategies for Success
7 Strategies for the Multiple-Choice Questions
IN THIS CHAPTER
Summary: The multiple-choice section of the AP Physics 2 exam contains a wide variety of question types. Some you may be unfamiliar with. This chapter contains strategies to attack this rogues’ gallery of questions.
There are 50 multiple-choice questions. All of them require deep understanding of physics.
You should practice a system when working multiple-choice questions. Make sure you know why the correct answer is correct and why the wrong answer is incorrect.
The last five questions will be “multiple-correct” questions. You will need to choose the two correct responses. There is no partial credit for getting only one correct.
Time . . . time . . . there is not enough time. Pace yourself so that you have an opportunity to work on every multiple-choice question. Answer every question because there is no guessing penalty.
The multiple-choice section is the first half of the exam. You have 90 minutes to answer 50 questions. Each question has four answer choices. The first 45 questions are the normal “one-correct” response that you are used to. The last five are “multiple-correct” questions where you need to choose both correct responses. There is no penalty for guessing, so be sure to answer every question. I’m going to repeat that so it sinks in—ANSWER EVERY QUESTION because it can only help your score. Don’t leave points on the table. Questions not answered = points not earned.
The multiple-choice questions do not involve simple recall of information, facts, or data. You are going to have to put your physics reasoning to work answering these questions. The questions will test all your skills. You will encounter graphs, lab-based questions, numerical problems, proportional and conceptual reasoning, problems with only symbols, ranking tasks, and questions with nothing but words. Some of the questions will seem easy to you and others will be gut-crunching hard.
How to Get Better at Multiple-Choice Problems
Most students read the stem of the question and begin to search for the correct answer. If what they are looking for is not given as a possible response, they guess or give up and move on. I’d like you to practice a different approach that will lead you to better results.
1. Read the stem of the question, paying close attention to any diagrams or graphs that can give you crucial information. (Remember that graphs give us three types of information. See Chapter 6.)
2. Ask yourself what kind of physics is involved. AP Physics 2 has seven major content areas:
• Electric Force, Field, and Potential
• Magnetism and Electromagnetic Induction
• Waves and Optics
• Quantum, Atomic, and Nuclear (also called Modern Physics)
Which content area does this problem fall into? Sometimes more than one content area will apply. This should take only a second to figure out.
3. Think about the tools from physics that would be useful in this situation. I always tell my students to put on their “physics glasses” and tell me what they see. You have six pairs of glasses to view the world:
• Energy glasses (What energy transformations are occurring? Is there work being done? Is energy conserved?)
• Force glasses (What are the forces and how are they affecting the system?)
• Momentum glasses (Are there any interactions of particles?)
• Kinematics glasses (What kind of motion is occurring?)
• Wave glasses (Is there any wave nature involved?)
• Nano glasses (Are the strange and wonderful behaviors of atoms and particles coming into play?)
Viewing the problem through these six “glasses” will help you see how to approach the problem. With practice, you will perform this step naturally.
4. Look at the answer choices. What are they like? Are they numerical, symbolic, graphical, or just words? Looking at your options gives you a clue on how to approach the problem. For instance, there may be numbers in the stem of the question and you start doing calculations only to find the answers are all symbols. A quick look at the answer choices will keep you from launching off in the wrong direction.
5. Eliminate any answer choice that can’t be correct by crossing it out. This will keep you from considering it again and wasting time. This will also improve your statistical chances if you have to take an educated guess.
These five steps will help you on exam day. As you prepare for the exam, here is a sixth step that will really amp up your physics skills and improve your exam score.
6. On every multiple-choice question, figure out and explain why the correct answer is correct. Just as important, figure out why each of the incorrect responses is wrong and explain why it is inconsistent with physics. This has two benefits. First, it deepens your physics knowledge to the point that will be expected on the exam. Second, the free-response section of the exam will ask you to justify and explain your reasoning. Practice this skill by writing down your justifications for each answer choice using “physics language.” Ask your teacher to review your reasoning if you need help on how to word your justification. This single practice step will improve your skills and score.
The last five multiple-choice questions (46—50) will be of this type of question. To remind you, there will be a short instruction paragraph separating these five multiple-correct from the previous “normal” single-correct questions. In addition, at the end of the stem of each multiple-correct you will see “Select two answers.” Finally, these questions will be numbered something weird like 130 through 135 and will be separated from the other multiple-choice questions on the answer document. So unless you are asleep, you can’t miss them.
You have to select both correct answers and none of the incorrect answers to get credit. This should not scare you. These questions are no harder than other multiple-choice questions. They just require a bit more thinking. In many cases you can determine one correct answer quickly. Then if you can eliminate a response that can’t be correct, you have a 50-50 shot on the last one. Use the steps outlined previously and you will do great.
Time: Pace Yourself!
Fifty questions in 90 minutes. That gives you 1.8 minutes per question or 9 minutes for every five questions. You don’t have time to fool around. Here are some strategies to help you with time management:
• This is not like the SAT where the questions start easy and get harder near the end. The AP exam is generally broken into topic chunks. There will be a few electricity problems, a couple of fluids problems, followed by one or two atomic/nuclear questions, etc. They are mixed up in bite-size pieces.
• You may be a superhero with circuits but a mortal in thermodynamics. The point is that the level of difficulty and variety of topics are sprinkled throughout the exam. Don’t get stuck on a problem you don’t know how to do and then run out of time without getting to those easy problems you know at the end of the exam.
• Skip any problems you don’t know how to do. Answer every problem you know first. You have secured the easy points. Now go back through the exam again and answer the ones you might know how to do now that your brain is warmed up. Cycle through the multiple-choice questions a third time if you have time.
• When time is running short, be absolutely sure to ANSWER EVERY QUESTION because it can only help your score.
• Take a watch with you to the exam to keep track of time remaining. (Some of you get psyched out by a ticking watch staring at you when you are under stress. If that is you, then skip the watch.)
• Practice makes perfect. You will have access to multiple-choice questions in your textbook or in class. Practice these questions under real testing conditions so that you can find your pace. (Remember the pace of 9 minutes for every five questions.) Ask your teacher for extra AP-style questions if the ones in your book are mostly numerical or not like what you see in this book.
Additional Strategies and Words of Wisdom
• Do not look for patterns in your answers. Every year I’ll have a student who says, “I had already picked answer choice (B) four times in a row so I decided to guess (A) since I hadn’t used it as much.” I like to remind students that they probably missed some of those four (B)s in a row! There is no pattern to the exam. There could be eight (D)s in a row, and 30 of the answers overall could be (A). Don’t bother looking for a pattern. Answer each question individually and move on.
• Remember the ranking tasks from Chapter 6. In these problems, you will be given a situation in which you’re going to have to rank answers from smallest to largest or largest to smallest. An example might be a circuit in which you’re asked to rank the power of the resistors in the circuit from largest to smallest.
• You are able to use a calculator for the entire AP Physics test, but it is not going to be all that important for you. The questions on the test are designed to test your knowledge of physics conceptually. Sure, there will be calculations on the test, but the numbers are not going to be the point of the test. In fact, the majority of the problems won’t have numbers.
• You will not find a simple “find the matching equation, plug in the numbers, and solve” problem on the test. Most of your calculation problems will involve multiple steps and will require more physics knowledge than simply plugging numbers into equations.