1D Kinematics: Motion in a Straight Line
A High School & College Primer on Position, Velocity, and Acceleration
Physics class just assigned kinematics, the exam is in a week, and the textbook reads like a legal document. Or maybe your student is staring at a velocity-time graph with no idea what any of it means. This guide is the shortcut.
**TLDR: 1D Kinematics** covers everything a high school or first-year college student needs to understand motion along a straight line — from setting up a coordinate axis and defining displacement all the way through the four constant-acceleration equations and free-fall problems. Six focused sections walk you through position, velocity, and speed (and why they're not the same thing), how to read x-t and v-t graphs without guessing, and why "negative acceleration" doesn't always mean an object is slowing down. The final section is a compact problem-solving playbook that targets the specific mistakes that cost students the most points on tests.
This is an ap physics 1 kinematics quick review guide in the truest sense: no filler chapters, no padding, no re-teaching things you already know. Every section leads with the one idea that matters, then backs it up with worked examples and real numbers. If you can work through the practice problems here, you're ready for class, a quiz, or an AP exam.
Ideal for students in AP Physics 1, college Physics 101, or any intro physics course that starts with kinematics. Also useful for tutors prepping a session or parents helping kids get unstuck.
Pick it up, read it in one sitting, and walk into your next exam with a clear head.
- Distinguish position, displacement, distance, velocity, speed, and acceleration, and use correct signs in 1D.
- Read and interpret position-vs-time and velocity-vs-time graphs, including slopes and areas.
- Apply the four constant-acceleration kinematic equations to solve standard problems.
- Handle free-fall problems, including objects thrown upward, using g as a constant downward acceleration.
- Set up problems by choosing a coordinate system, identifying knowns/unknowns, and checking answers for physical sense.
- 1. Position, Displacement, and the Choice of AxisIntroduces the 1D coordinate system and the distinction between distance traveled and displacement.
- 2. Velocity and Speed: Average vs InstantaneousDefines average and instantaneous velocity, contrasts velocity with speed, and connects velocity to the slope of a position-time graph.
- 3. Acceleration and Reading Motion GraphsIntroduces acceleration, explains why negative acceleration isn't always 'slowing down,' and shows how to extract motion information from x-t and v-t graphs.
- 4. The Four Constant-Acceleration EquationsDerives and applies the standard kinematic equations for constant acceleration, with a strategy for choosing which equation to use.
- 5. Free Fall and Vertical MotionApplies 1D kinematics to objects under gravity, including thrown-upward problems where velocity changes sign.
- 6. Problem-Solving Strategy and Common PitfallsA compact playbook for setting up any 1D kinematics problem, plus the mistakes that cost students the most points.