Definition:Acceleration
Definition
The acceleration $\mathbf a$ of a body $M$ is defined as the first derivative of the velocity $\mathbf v$ of $M$ relative to a given point of reference with respect to time $t$:
- $\mathbf a = \dfrac {\d \mathbf v} {\d t}$
Colloquially, it is described as the rate of change of velocity.
It is important to note that as velocity is a vector quantity, then it follows by definition of derivative of a vector that so is acceleration.
Dimension
Acceleration has dimension $\mathsf {L T}^{-2}$.
Units
The SI unit of acceleration is the metre per second squared: $\mathrm {m \, s^{-2} }$.
The CGS unit of acceleration is the gal: $\mathrm {Gal}$.
The FPS unit of acceleration is the foot per second squared $\mathrm {ft \, s^{-2} }$.
Symbol
The usual symbol used to denote the acceleration of a body is $\mathbf a$.
Acceleration in a Straight Line
Let $P$ be a particle in motion along a straight line $\LL$ with acceleration $\map {\mathbf a} t$ as a function of time $t$.
It is conventional to align $\LL$ along the $x$-axis of a Cartesian coordinate system such that the $\mathbf a$ can be expressed as $a \mathbf i$.
Then the unit vector of the component vector $a \mathbf i$ is suppressed, and $\map {\mathbf a} t$ is treated as a scalar quantity $\map a t$.
Also see
- Results about acceleration can be found here.
Historical Note
The first person to study the acceleration of a particle moving along a general curve was first studied by Leonhard Paul Euler.
He was also the first to treat acceleration as a vector.
Linguistic Note
The word acceleration comes from the Latin for to add speed.
Sources
- 1921: C.E. Weatherburn: Elementary Vector Analysis ... (previous) ... (next): Chapter $\text I$. Addition and Subtraction of Vectors. Centroids: Definitions: $1$. Scalar and vector quantities
- 1937: Eric Temple Bell: Men of Mathematics ... (previous) ... (next): Chapter $\text{VI}$: On the Seashore
- 1951: B. Hague: An Introduction to Vector Analysis (5th ed.) ... (previous) ... (next): Chapter $\text I$: Definitions. Elements of Vector Algebra: $1$. Scalar and Vector Quantities
- 1965: Seth Warner: Modern Algebra ... (previous) ... (next): Chapter $\text {V}$: Vector Spaces: $\S 26$. Vector Spaces and Modules
- 1966: Isaac Asimov: Understanding Physics ... (previous) ... (next): $\text {I}$: Motion, Sound and Heat: Chapter $2$: Falling Bodies: Acceleration
- 1966: Isaac Asimov: Understanding Physics ... (previous) ... (next): $\text {I}$: Motion, Sound and Heat: Chapter $3$: The Laws of Motion: Forces and Vectors
- 1970: George Arfken: Mathematical Methods for Physicists (2nd ed.) ... (previous) ... (next): Chapter $1$ Vector Analysis $1.1$ Definitions, Elementary Approach
- 1989: Ephraim J. Borowski and Jonathan M. Borwein: Dictionary of Mathematics ... (previous) ... (next): acceleration: 1.
- 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): acceleration
- 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): acceleration
- 2008: Ian Stewart: Taming the Infinite ... (previous) ... (next): Chapter $8$: The System of the World: Newton
- 2014: Christopher Clapham and James Nicholson: The Concise Oxford Dictionary of Mathematics (5th ed.) ... (previous) ... (next): acceleration
- 2014: Christopher Clapham and James Nicholson: The Concise Oxford Dictionary of Mathematics (5th ed.) ... (previous) ... (next): rate of change
- 2021: Richard Earl and James Nicholson: The Concise Oxford Dictionary of Mathematics (6th ed.) ... (previous) ... (next): acceleration