2 Understanding the Exam: The AP Physics 1 Revolution

The AP physics exam requires less calculation and more written explanations.

The chapter explains what the test is like and how it is different from traditional physics tests.

The AP physics exam is more focused on explaining and applying the concepts of physics than on getting the "right" numerical answer to a problem.

There is no walk in the park for the AP physics 1 exam.

It requires a deeper understanding of physics despite the fact that it has less math and fewer topics.
The AP physics 1 exam is more difficult than a high school physics exam.

The AP physics 1 exam is not the same as what your father or older sister took.

A profound understanding of the science of physics has been added to the AP physics 1 curriculum.

In the 70s and 1980s, a typical physics professor gave lectures that focused on math ematics to first-year students and then administered exams that demanded clever algebraic manipulation.

College physics was reflected in the AP physics B exams of that era.

In the 1990s, a new generation of physics professors promoted a different kind of physics teaching that demanded more explanation and less skill.

The meaning of the math became more important than it was.

When the College Board received a grant to redesign their science courses in the early 2000s, the curriculum design committee decided to move even further away from calcula tion and more toward verbal explanation.

They reduced the number of topics on the new AP physics exams.
They thought that the exam could be more demanding if there was more writing and more detailed explanations in the responses.

The College Board's AP program is designed to give advanced high school students access to college-level courses.

The goal has been to create exams that mimic the content and level of typical courses at an American university.

In redesigning their science courses, the development committees wanted to reflect best practices as well as the content and difficulty level of the best college courses.

The best college classes include demonstrations, laboratory work, and descriptive as well as calculational physics.

If you understand the test and what's being tested, you'll do better on a test.

The mechanics will dominate the exam.

Motion, force, momentum, energy, and rotation are some of the topics of mechanics.
The study of electricity is limited to the force between charged particles.
AP physics 1 contains less material than the old AP physics B course did.
AP physics 1 is designed to replicate the first semester of a freshman college course.
The second-semester material is covered in physics 2.

The current AP physics C exams and the old AP physics B exam were developed with the understanding that students would already have taken a high-school-level introduction to physics.

Many high school students want to go into physics at the college level, and are ready to do so.
AP Physics 1 was written to help these students succeed.
There is a decrease in the amount of material covered.
If you've never seen physics before, you'll have the time in AP Physics 1 to develop both your content knowledge and physics reasoning skills to perform well on the exam.

There are only three high-school-level mathematical skills you need in order to understand AP Physics 1 material.

You covered these things in geometry courses.

You don't need any of the things you're studying in precalculus or Algebra II.

You have to use numbers occasionally.

There are many myths about physics in math class.

Your teacher will show you how to do a type of problem, and then you will do several variations of that same problem for homework.
The answer to one of these problems could be 30,000,000.

There is a problem with manipulating random numbers to get an answer.

The answer may be 30,000,000 joules, or 30,000,000 seconds, but not 30,000,000.

The fundamental point of physics is missing if you don't see the difference.

Thirty million seconds is a time, not a few hours or a few minutes, and it could be the energy of an antitank weapon or the energy of an aircraft carrier raised up a foot.

The extensions of these concepts as "derivatives" and "integrals" are useless in AP physics 1.

It would cost $1 to use this much electrical energy in your house.

Get to know the exam and set up your study program responses are completely different.

You're doing a math problem if you just give a number as an answer.
You may claim to understand physics if you can explain the meaning of a result.

Sometimes you'll be asked to make numerical calculations.

Quantitative reasoning means explaining why calculations come out the way they do.

You'll be asked if quantities increase or decrease by looking at the relevant equation and performing the calculations.
When one equation with a single variable can be written, or when two equations with two variables can be written, or even when three equations with three variables can be written, is a problem that can be solved.
You won't be asked to solve even mildly complicated multivariable problems, but you must understand why they are or aren't solvable.

Predicting how the structure of an equation will affect the result of a calculation is called "semiquantitative" reasoning.

Increasing a variable in the numerator increases the quantity being calcu lated while decreasing the quantity being calculated.

If the term is squared, the entire quantity is doubled, except if it is square-rooted.

"Calculate the acceleration of the 250-g cart" is a legiti mate question on the AP physics 1 exam.

More often the question will be rephrased to get at the heart of your ability to reason about physics, not just at your math skills.
To justify your ranking, you need to rank the carts from greatest to least.

Explain how you would use a graph to determine the cart's speed.

Every physics problem that asks for calculation, quantitative reasoning, or semiquantitative reasoning is asking for an experimental prediction.

Every calculation can be verified by an experimental measurement.

A math problem that you might see in an Algebra 1 class is the use of an equation to calculate a cart's acceleration.
You can pull out a 250-g cart and a motion detector from a cabinet and measure the cart's acceleration.
If you set up the situation that was described in the problem, you'd better get an acceleration of 2.8 m/s per second; otherwise, either the calculational approach was incorrect or the experiment was set.

AP physics 1 has a lot of problems that can be set up for experimental measurement within the realm of most people's experience.

There are carts in your classroom.

To take the AP physics 1 revolution 17 exam you have to take a video of cars on a freeway or roller coaster.

If you're familiar with using force probes, motion detectors, photogates, and so on., then computerized data collection should be part of your classroom experience.
To analyze the data produced by experiments, be prepared to describe an experiment that uses laboratory equipment.

The table of the cart's speed was produced in the laboratory.

The data can be used to determine the car's speed.

In the laboratory, a student measures the cart's speed at 4.1 m/s per second, but the cart's speed is calculated to be 2.8 m/s per second.

Students are expected to have done a set of experiments in AP Biology.

Common experiments will be referred to in biology exam questions.
This approach is different from AP physics.

AP physics requires experimental skills.

25 percent of class time must be spent doing live, hands-on laboratory exercises.
The actual nature of those exercises is left to the teacher.
Lab work can be done with almost every AP Physics 1 question that can be set up as an experiment.
AP physics exams demand creativity in lab work.

It's important that you don't think of the "lab" as a place where you follow a procedure to produce a canned result that matches your teacher's expectation.

Think of the lab as a place to play, a place to re-create the calculational problems you've been working on in class.
The lab is a place where you can test your ideas.

No one expects you to win a prize in your lab.

It is expected that you go beyond the "facts" of physics.

Each physics fact has evidence from an experiment.

You should be able to articulate how an experiment could be designed to test the validity of any fact, and you should be able to use equipment to make a measurement of any quantity that might show up in a calculational problem.

The "AP Central" portion of the College Board's official website contains information about the course audit.

The free-response questions on the AP Physics 1 Exam will be similar to those on the AP Biology or AP Economics exams.

Do not expect to answer only in numbers and mathematical symbols.

You don't need to develop your story telling skills.

The writing is easy to understand.
A perfect response to the AP Physics 1 Exam could cause a lot of problems for your English teacher.
Your language and vocabulary should be simple, not flow ery.
You don't need to have a different sentence structure.
You don't need to make your reader pay attention to paragraphs and ideas.

Don't worry about how your writing sounds to a professional.

Imagine if the person reading your writing is a physics student.
Don't explain your answers in a way that a college professor would, simply and clearly, but completely.

Write on your problem sets.

Even if your teacher doesn't explicitly require them, practice using these elements in every solution in physics class.

If a student doesn't use at least three of these four elements in their response to a homework question, they lose significant credit in my class.

Don't be afraid to draw diagrams.

If you want to do your homework on graph paper or unlined paper, try it.
Think of the paper as a blank canvas that needs to be filled in with your understanding of the problem.

The lined notebook paper is too restrictive.

It means that you should be writing rows of words.
Words can be written on a diagram with arrows.
There are graphs and pictures that can be drawn.
It's not necessary to place equations one after the other in columns.
The purpose of the equations in the problem's solution should always be described in the series of equations.

You'll be well prepared for the exam because you'll be practicing interpreting physics explanations.

You'll be asked to use multiple representations of concepts on the free-response questions, but don't worry: you'll be asked for such interpretations on the multiple-choice section.

As the new exams were being developed, it became clear that the increased demands for writing, for experimental interpretation and description, and for multiple representations of physics concepts would require a lot of time and thought.

Students need to be given time to respond in a complete way, and that's what the commit tee in charge of creating AP Physics 1 agreed on.

Students with strong physics abilities are often pressed for time on exams.

The rule of thumb was to spend about one minute per point on a multiple choice question, 15 minutes on a 15-point free response question, and so on.
Students were told to work quickly, ignoring in-depth thought for quick solution methods.

AP Physics 1 is only half as long.

In 90 minutes, you'll get 50 multiple-choice questions.
You can think carefully about some if you knock a few off quickly.
There will be two long 12-point questions and three short 7-point questions in the free-response section.
If you don't work steadily without dawdling, you might run out of time on the exam.
You have time to think before you write, and then you have time to write everything you need to say.

AP read ers are as good at recognizing baloney as they are at recognizing good physics.

You will be less likely to get points for using a correct equation.
While partial credit on the free response will be available, it will not be possible unless you have a good understanding of physics.

When the scores come out after the exam, expect wailing and gnashing of teeth because too many teachers and students are still thinking of physics.

You know that a true understanding of physics requires that you be able to solve problems, explain how you solved them, and explain why.
Those with gnashed teeth still believe that just producing an answer is enough.