Position, velocity and acceleration
Describe a point's motion on a chosen straight axis, then connect signed changes, instantaneous rates and one exact set of position, velocity and acceleration graphs.
Key knowledge
In a chosen reference frame, instantaneous velocity is the time derivative of position and instantaneous acceleration is the time derivative of velocity.
Values and equations
v = dr/dt; a = dv/dt
- r
- Position vector in the chosen frame m
- v
- Velocity vector m s⁻¹
- a
- Acceleration vector m s⁻²
- t
- Time s
Conditions and scope
- Velocity requires the position derivative; acceleration also requires the relevant derivative of velocity, or second derivative of position, to exist.
- The relations describe motion; they do not alone specify its cause.
Sources · 6
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
- Chapter 4: One Dimensional Kinematics (2022 corrected notes)Peter Dourmashkin — MIT OpenCourseWare, Classical Mechanics: MIT 8.01 Course NotesTeaching resource · PDF
- Chapter Two: Motion in a Straight Line (reprint 2026–27)National Council of Educational Research and Training — Physics Part I, Class XITeaching resource · PDF
- 21.2 Reference frameSiyavula — Physical Sciences Grade 10, English web textbookTeaching resource
- University Physics, volume 1: Average and Instantaneous AccelerationSamuel J. Ling, Jeff Sanny and William Moebs / OpenStax, Rice UniversityTextbook chapter
Samuel J. Ling, Jeff Sanny and William Moebs — OpenStax, Rice University (2016)2 sources
- University Physics Volume 1: 3 2 instantaneous velocity and speedSamuel J. Ling, Jeff Sanny and William Moebs — OpenStax, Rice University (2016)Textbook chapter
- University Physics Volume 1: 4 1 displacement and velocity vectorsSamuel J. Ling, Jeff Sanny and William Moebs — OpenStax, Rice University (2016)Textbook chapter
Evidence and review
OpenStax 3.3, equation 3.9 and its relation to the derivative of position.
2026-10-10 · Classical kinematic definitions only; units and derivative requirements checked.
Foundational review
2026-10-10 · Fresh primary-source inspection of the complete compact record, including every statement, equation, quantity and material condition, followed by independent AI editorial review. This check does not certify all linked lessons or every passage of every cited publication.
Sources from other places
Scope or convention differs
In one-dimensional motion, velocity and acceleration are successive time derivatives of position.
The chapter verifies the one-dimensional case; the repository also states the spatial-vector form and frame requirement.
National Council of Educational Research and Training (NCERT)
- Motion in a Straight Line · Physics (2026–27 reprint) IndiaEnglish
2.2 Instantaneous velocity; 2.3 Acceleration
- Motion in a Straight Line · Physics (2026–27 reprint)
Related articles
Position, displacement, velocity, and acceleration ↗Entry details
Permanent link to this entry ↗- Record identity
- motion
- Revision
- reference-core.1
- Published lesson seed
- position-displacement-velocity-acceleration