AP Physics 1 · Exam guide
AP Physics 1 Qualitative/Quantitative Translation Explained: Connecting Equations and Explanations
The qualitative/quantitative translation question asks you to move between math and words. You calculate a quantity, then use the same physics to explain what would happen if something changed, or you judge a claim using your equation. The numbers below are made up for practice.
The two directions of translation
| Direction | What you do |
|---|---|
| Math to words | Use an equation to explain or evaluate a claim in a sentence. |
| Words to math | Turn a described relationship into an equation or a sketch of a graph. |
A worked example
A 2.0 kg block is pulled across a table by a 10 N horizontal force. Friction exerts 4 N on the block. Find its acceleration.
- Net force: \(F_{net} = 10 - 4 = 6\) N.
- Acceleration: \(a = F_{net}/m = 6/2.0 = 3.0\) m/s\(^2\).
Translation: A student claims that doubling the applied force will double the acceleration. Evaluate the claim.
It states a verdict but does not use the physics to show why.
It uses the equation to test the claim and explains the reason.
A habit that earns the points
- Write the equation first, then connect each symbol to the situation.
- Give the result with units, and then say in a sentence what it means.
- When asked to compare, calculate both cases and say which is larger and why.
- When asked how a quantity changes, name the other quantities that stay constant.
Common mistakes
- Giving a verdict with no equation or number behind it.
- Treating the net force as the applied force and forgetting friction.
- Saying "it increases" without saying why or by how much.
- Mixing up the units, such as writing newtons for acceleration.
Frequently asked questions
What is a qualitative/quantitative translation question?
A free-response question that has you move between an equation and a written explanation, for example by checking a claim with a calculation.
Do I need numbers in my explanation?
When the question gives numbers, use them. A claim backed by a calculation is stronger than one backed by words alone.
How do I know which equation to use?
Start from the physics principle that describes the situation, such as Newton's second law, and write it in terms of the quantities in the question.
What value of g should I use?
Use 10 m/s squared, which this course uses to match the current exam.
Where can I find the official scoring rules?
Exam formats change a little from year to year, so check the current course and exam description on the College Board site before test day.
Keep practicing
Every lesson in the AP Physics 1 course ends with practice items and an Exam focus box, and every unit has a ten-question practice set with worked answers. These free lessons also build the skills the free-response section tests:
See the AP Physics 1 course Free lessons and lesson list
Other free-response guides:
- AP Physics 1 FRQ Guide: Experimental Design, Translation and Written Arguments
- AP Physics 1 Experimental Design Question Explained: How to Plan an Experiment and Use the Data
- AP Physics 1 Paragraph Argument Explained: Writing a Claim, Evidence and Reasoning Answer
AP is a registered trademark of the College Board, which is not affiliated with and does not endorse this site. This guide is our own explanation of the question types and scoring. For the official scoring guidelines, see the College Board.