Introduction - SAT Physics Subject Test

SAT Physics Subject Test


The SAT Subject Tests are a series of one-hour exams developed and administered by Educational Testing Service (ETS) and the College Board. Unlike the SAT, the SAT Subject Tests are designed to measure specific knowledge in specific areas. There are many different tests in many different subject areas, such as biology, history, French, and math. They are scored separately on a scale from 200 to 800.

How Are SAT Subject Tests Used by College Admissions?

Since the tests are given in specific areas, colleges use them as another piece of admissions information and, often, to decide whether an applicant can be exempted from college course requirements. For example, a certain score may excuse you from a basic science class or a foreign language requirement.

Should I Take the SAT Subject Tests? How Many? When?

About one third of the colleges that require SAT scores also require that you take two or three SAT Subject Tests. Your first order of business is to start reading those college catalogs and websites. College guidebooks, admissions offices, and guidance counselors should have this information as well.

As to which tests you should take, the answer is simple. Take the SAT Subject Tests

· on which you will do well.

· that may be required by the colleges to which you are applying.

Some colleges have specific requirements, while others do not. Again, start asking questions before you start taking tests. Once you find out which tests, if any, are required, part of your decision making is done. The next step is to find out which of the tests will highlight your particular strengths. Colleges that require specific tests generally suggest that you take two subject tests from the following five groups: laboratory science, history, foreign language, math, and English literature.

As for timing, take the tests as close as possible to the corresponding coursework you may be doing. If you plan to take the SAT Physics Subject Test, for example, and you are currently taking physics in high school, don’t postpone the test until next year.

When Are the SAT Subject Tests Offered?

In general, you can take from one to three Subject Tests per test date in October, November, December, January, May, and June at test sites across the country. Not all subjects are offered at each administration, so check the dates carefully.

How Do I Register for the Tests?

To register by mail, pick up The Paper Registration Guide for the SAT and SAT Subject Tests at your guidance counselor’s office. You can also register at the College Board website, This site also contains useful information, such as the test dates and fees. If you have questions, you can talk to a representative at the College Board by calling 1-866-756-7346 from within the United States or 212-713-7789 from outside the country.

You may have your scores sent to you, to your school, and to four colleges of your choice. Additional reports will be sent to additional colleges for—you guessed it—additional money. Scores are made available to students via the College Board’s website. To find out about the timeline of when the scores are made available, visit

What’s a Good Score?

That’s hard to say, exactly. A good score is one that fits in the range of scores for which the college of your choice usually accepts. However, if your score falls below the normal score range for Podunk University, that doesn’t mean you won’t go to Podunk University. Schools are usually fairly flexible in what they are willing to look at as a “good” score for a particular student.

Along with your score, you will also receive a percentile rank. That number tells you how you fit in with the other test takers. In other words, a percentile rank of 60 means that 40 percent of the test takers scored above you and 60 percent scored below you.

A Couple of Words about Score Choice

As of February 2009, you can choose which SAT Subject Test scores you want colleges to see. This is great news! For one thing, if you take more than one SAT Subject Test on a given test date, you’ll be able to choose which tests from that date you’d like to submit to colleges. So if, for example, you take the French test followed by the chemistry test, but you don’t think the chemistry test went very well, you can simply opt out of having that chemistry score sent to your schools.

The score reporting policy is optional for students. This means that you aren’t required to opt in and actively choose which specific scores you would like sent to colleges. If you decide not to use the score-reporting feature, then all of the scores on file will automatically be sent when you request score reports. For more information about the new score-reporting policy, go to the College Board website at

What’s on the SAT Physics Subject Test?

The SAT Physics Subject Test contains 75 multiple-choice questions, and the time limit is 1 hour. The topics covered (which are listed below) are those most likely to be studied in a standard college-prep level high school physics course. The following list includes the major topics coveredon the SAT Physics Subject Test, along with the corresponding chapters in this book and an approximate percentage of the questions on each.

Approximate Percentage of Major Topic Questions

Mechanics (Chapters 27)
Kinematics, Dynamics, Energy and Momentum, Circular Motion and Rotation, Vibrations and SHM, Gravity


Electricity and Magnetism (Chapters 812)
Electric Fields, Forces, Potentials, Magnetic Fields and Forces, Electric Circuits, Electromagnetic Induction


Waves and Optics (Chapters 1314)
General Wave Properties, Doppler Effect, Reflection and Refraction, Interference, Diffraction, Polarization, Ray Optics


Thermal Physics (Chapter 15)
Temperature and Heat, Kinetic Theory, Thermodynamics


Modern Physics (Chapter 16)
Quantum Phenomena, Atoms, Nuclear Physics, Relativity,


History, Overlapping Questions, Graph Analysis, Measurement, Math Skills, Astrophysics, Superconductivity, Chaos Theory


Since you have only about 45 seconds (on average) to answer each question, you won’t be surprised to find that the math on the SAT Physics Subject Test is pretty straightforward; any mathematical calculations that do come up require no more than basic arithmetic, algebra, and trigonometry. The numbers will be simple, because you are not allowed to use a calculator on the test, and no formula sheet is given (or can be brought). You also cannot bring scratch paper; all scratch work must be done directly in the test booklet.

How Is the Test Scored and How Well Do I Need to Do?

On this test, each of the 75 questions is followed by 5 possible responses (A through E), and your job, of course, is to choose the best answer. Your raw score is equal to the number of questions you got right minus a fraction of the number of questions you answered wrong, rounded to the nearest whole number. If you leave a question blank, it isn’t counted as either right or wrong. For example, let’s say that of the 75 questions, you got 42 right, 26 wrong, and you left 7 blank. They figure out your raw score as follows:

42 – (26) = 35.5 — round to → raw score = 36

Then they convert this raw score to a scaled score. The SAT Subject Test scores are reported on a 200 to 800 scale (in multiples of 10). So your raw score of 36 may be converted to a scaled score of, say, 650. This is the score that’s reported to you.

How would this score of 650 measure up? The averages vary slightly from administration to administration, but the average score on the November 1995 SAT Physics Subject Test was 653, the average score on the May 2000 test was 635, and the average score for 2007 college-bound seniors was 647, so a score of 650 would be considered at or above average. Notice that you can get more than a third of the questions wrong and still get an average score! Naturally, different colleges have different admission criteria. Some may report the average scores of their entering freshmen, so talk with your school counselor and check with the admissions offices of the colleges in which you’re interested to see if they release their SAT averages.

Some Test-Taking Tips

When approaching the practice tests or the actual SAT Physics Subject Test, there are some helpful strategies you can use to help maximize your score.

Know the Directions to Part A Now

There are two parts to the SAT Physics Subject Test: Part A and Part B. Part A, which accounts for the first set of questions (typically from 12 to 23), consists of several groups of questions (typically 2 to 4 per group). The questions within any one group all relate to a single situation, and the five possible answer choices are actually given before the questions. The most important thing to remember is that in Part A, an answer choice may be used once, more than once, or not at all in each group. For example, if the first group of questions in Part A are questions 1 to 4, then the answer to question 1 might be B, question 2 could be D, question 3 could be A, and question 4 could be D again. Note that in this group choice D was the correct answer twice and choices C and E were not used at all. The questions on Part A of the test actually look like the following:

Questions 1-3 refer to the following quantities:

(A) Wavelength

(B) Frequency

(C) Period

(D) Wave speed

(E) Amplitude

1. Which quantity is a fixed constant for all electromagnetic waves in a vacuum?

2. For a standing wave on a string that is fixed at both ends, which quantity is inversely proportional to the wave speed?

3. What is the distance between adjacent crests on a traveling wave?

(The answers to these questions are D, C, and A, in case you’re curious.) Be prepared for this first section of the SAT Physics Subject Test, and don’t waste valuable time by rereading the directions to Part A on the day of the test. Know the directions by heart.

Part B consists of the remaining questions. While some of the questions may be in groups of 2 or 3, all the questions in Part B are of the usual “question followed by 5 answer choices” variety, and each has a unique correct answer. The following is an example of a Part B question:

14. A block of mass m slides with constant speed down a ramp whose incline angle is θ. If F1 is the magnitude of the gravitational force acting parallel to the ramp and F2 is the magnitude of the normal force acting on the block, what is the value of F1/F2 ?

(A) m tan θ

(B) m cot θ

(C) 1

(D) cot θ

(E) tan θ

The answer to this problem is E.

Know That You Can Skip Questions Entirely

You might think that to get a great score, you need to answer nearly every question correctly. But don’t stress out—this isn’t the case at all. It’s perfectly acceptable to skip some questions entirely, and, in fact, if you do this you’ll have more time to answer questions that are easier for you—ones you have a better chance of getting right.

Perhaps some statistics will show you that it’s okay to skip questions. The average score on the SAT Physics Subject Test is about 650 (on the familiar 200 to 800 scale). Scoring above 700 would put you in the top third of all test takers. You could skip about 30—that’s right, 30—questions and still get a 700. If your goal is a 750, which would place you in the top fifth of all test takers, you could skip about 20 questions. And you could skip about 10 questions and still earn the top score of 800. Takes some of the pressure off, doesn’t it?

Of course, to get those scores while skipping all of those questions, you would need to answer all the others correctly. It’s probably more than likely that you’d get a few wrong. So let’s look at a more realistic sample-test scenario. There are 75 questions on the SAT Physics Subject Test. As described before, you get 1 point for each question you answer correctly, 0 points for any question you skip (and thus leave blank), and point is subtracted for each question you answer incorrectly. So, let’s say you skip 13 questions entirely, answer 50 questions correctly, and answer 12 incorrectly. Your raw score would be 50 – (12) = 47, which would convert to a scaled score of about 700 to 720. If you had skipped more questions, 17 instead of 13, and still answered 50 correctly (but 8 incorrectly), your raw score would be even higher: 50 – (8) = 48, which would be converted to a scaled score of about 720 or higher.

So the strategy is clear: If you get to a question that you know nothing about—one on which you can’t eliminate even a single answer choice, don’t let it fluster you—just skip it.

Process of Elimination Is Your Best Friend

On the SAT Physics Subject Test, like so many other multiple-choice tests, the Process of Elimination (POE for short) is your most valuable test-taking strategy. One of the advantages to taking a multiple-choice test is that the correct answer to every question is right there on the page! Often it’s easier to identify (and eliminate!) wrong answer choices than it is to figure out the correct one. So after reading a question, the first thing you should do is read the answer choices. If you know a choice can’t be right, cross it out. And remember: If even part of an answer choice is wrong, it’s all wrong.

Also, it’s important to notice that if two (or more) choices are equivalent—that is, if two or more choices would be valid together—then you can automatically eliminate all of them. After all, each question has just one correct answer; it can’t have two (or more). As an example, look at Question 21 on this page. By Newton’s Second Law, Fnet = ma, choices B and C are equivalent because if a were zero, then the Fnet would also be zero (and vice versa); that is, if B were correct, then C would also have to be correct. Since the question can’t have two correct answers, eliminate both B and C.

Use POE as much as you can, because even if a question is difficult, as long as you are able to eliminate one or more choices, it is generally to your advantage not to skip the question, but instead to guess among the remaining choices and move on.

Never Spend Too Much Time on Any One Question

The questions on the SAT Physics Subject Test are not organized by level of difficulty, and every question on the test—whether it’s easy, medium, or difficult—is worth the same amount: one point. You don’t get extra credit for correctly answering a difficult question. If you see a question that seems tough, try to eliminate some choices. If you can’t, just skip it. Never waste time agonizing over a tough question when there are easier questions you can answer.

Bubble in Your Answers in Groups

Going back and forth from the test book to your answer sheet after every single question can eat up lots of time. A better strategy is to bubble in your answers in groups. As you finish a question, write the answer as a big capital letter directly underneath the question number. After you’ve finished a page or two, transfer your answers to the answer sheet. Of course, make sure you bubble in your answer sheet correctly; as you get to each question number, say it (to yourself), along with the letter you’ve written down below the question number, and transfer that to the answer sheet. If you’ve skipped a question, be sure to leave that one blank on the answer sheet. It’s important to keep your eye on the time because after time is called, you will not be allowed to bubble in anything on your answer sheet. So when you’re getting to the end of the test (say, the last 5 minutes), it’s a good idea to bubble in your answers one at a time, just to be sure you get them all in before time is called.

Make Two Passes Through the Test

The point of the two-pass system is to make sure you answer all the questions you find easy first before spending time on questions you find more difficult. Read through the questions in the order in which they’re presented in the test book. If you can answer one relatively quickly, do so, and write the answer as a big capital letter directly below the question number. If it’s a question that you think you could answer, but it looks like it might take a little while, circle the question number, and move on. If it’s a question that you decide should be skipped entirely, put a big “X” through the question itself and then place a dash directly underneath the question number. As you move through the test, periodically check your watch to see how you’re doing on time (remember, the time limit is one hour). Continue like this—deciding whether each question is answerable now, later, or never—until you reach question number 75 (which is always the last question). You have now completed your first pass through the test.

Next, go back to the beginning and make your second pass. Find the questions you circled and try them again. If your second attempt at these questions is bogging you down, just pick one of the answer choices that you didn’t eliminate, write the letter below the question number, and move on. Continue like this, either bubbling in your answers in groups, or one at a time if time is growing short, and complete your second pass. Finally, if you have any time remaining, consider starting a third pass. Of course, the numbers of questions you decide to do immediately, do later, or not do at all are entirely up to you, and will vary from test-taker to test-taker. Do make sure that you get to the end of the test, because there may be easy questions lying in wait there, however many questions you do or skip.

21. A ball is thrown straight upward and falls back to the ground 3 seconds later. At the moment the ball reaches its highest point

(A) its potential energy is minimized

(B) its acceleration is zero

(C) the net force on the ball is zero

(D) its velocity is changing

(E) the force of gravity on the ball is greater than when it was first thrown

Question 21

This is what a question
you can answer on the
first pass should look like.
Use POE and write your
answer under the question


(A) m(0.8c)2

(B) ( –1)mc2

(C) mc2

(D) ( –1)mc2

(E) mc2

Question 22

Skip questions if you
cannot eliminate any
answers. Cross out
questions you choose to
skip so you don’t waste
time during your second

The figure above shows the two unbalanced forces acting on a block. If the velocity of the block is to the left, then

(A) the work done by F1 is positive

(B) the work done by F2 is negative

(C) the momentum of the block is decreasing

(D) the net force is in the same direction as the velocity

(E) the kinetic energy of the block is increasing

Question 23

Circle questions you want
to return to during your
second pass. This allows
you to come back
to time-consuming
questions if you have time
at the end of the test.

How Should I Prepare for the Test?

Most students take the SAT Physics Subject Test after they’ve taken a year-long college-prep course in physics at their high schools. The test is offered in May and June, so you can take it near the end of the school year while the material is still fresh. It’s offered again in the fall (October, November, and December), so you have the option to take it at these times as well.

Naturally, it’s important to be familiar with the topics—to understand the basics of the theory, to know the definitions of the fundamental quantities, and to recognize and be able to use the equations. Then, you should get some practice applying what you’ve learned to answering questions like the ones you’ll see on the test.

This book contains hundreds of practice questions that review all of the content areas covered on the test. Each chapter (except the first) is followed by sample multiple-choice questions. One of the most important aspects of this book is that answers and explanations are provided for every example and question. You’ll learn as much—if not more—from actively reading the explanations as you will from reading the text and examples.

In addition, two full-length practice tests are provided. These are designed to simulate a real SAT Physics Subject Test and will give you additional practice for the real thing. Again, a complete solution is provided for every question in both of these sample tests. The difficulty level of the examples and questions in this book is at or slightly above SAT Subject Test level, so if you have the time and motivation to attack these questions and learn from the solutions, you should feel confident that you will do your very best on the actual test.

Practice test questions are also available directly from the College Board on its website, The College Board also publishes a book entitled The Official Study Guide for All SAT Subject Tests. You can purchase this book at your local bookstore, through an online bookstore, or through the College Board’s website.

You can also go to the website to get information about the SAT Physics Subject Test, including test descriptions, test dates, and test centers, and you can register for the SAT Subject Tests online.

I wish you all the best as you study for the SAT Physics Subject Test. Good luck!

Steve Leduc