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Wiki Markup
Composition Setup
 Excerpt
hiddentrue
System: One point particle moving in one dimension either because it's constrained to move that way or because only one Cartesian component is considered. — Interactions: Constant force (in magnitude or in its component along the axis). 
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Introduction to the Model
Description and Assumptions
This model is applicable to a single point particle moving in one dimension either because it is physically constrained to move that way or because only one Cartesian component is considered. The force, or component of force along this direction, must be constant in time. The force can be in the same direction of motion or in the opposite direction of motion. Equivalently, the model applies to objects moving in one-dimension which have a position versus time graph that is parabolic and a velocity versus time graph that is linear. It is a subclass of the One-Dimensional Motion (General) model defined by the constraint da/dt = 0 (i.e. 
}{composition-setup}
{excerpt:hidden=true}{*}System:* One [point particle] moving in one dimension either because it's constrained to move that way or because only one Cartesian component is considered. --- *Interactions:* Constant force (in magnitude or in its component along the axis). {excerpt}

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h4. Introduction to the Model

h5. Description and Assumptions

This model is applicable to a single [point particle] moving in one dimension either because it is physically constrained to move that way or because only one Cartesian component is considered.  The [force], or component of force along this direction, must be constant in time. The [force] can be in the same direction of motion or in the opposite direction of motion.  Equivalently, the model applies to objects moving in one-dimension which have a [position versus time graph] that is parabolic and a [velocity versus time graph] that is linear.  It is a subclass of the [One-Dimensional Motion (General)|One-Dimensional Motion (General)] model defined by the constraint da/dt = 0 (i.e. 
 a(t)=constant).



{info}
 Info
Multi-dimensional 
 
 motion 
 
 can 
 
 often 
 
 be 
 
 broken 
 
 into 
 
 components, 
 
 as 
 
 in 
 
 the 
 
 case 
 
 of 
 [
projectile
] 
 motion. 
  
 In 
 
 this 
 
 manner, 
 
 the 
 
 1-D 
 
 motion 
 
 with 
 
 constant 
 
 acceleration 
 [
model
] 
 can 
 
 be 
 
 employed 
 
 to 
 
 describe 
 
 the 
 [
system's
|system] 
 motion 
 
 in 
 _
any
_ 
 situation 
 
 where 
 
 the 
 [
net 
 
 force
] 
 on 
 
 the 
 [
system
] 
 is 
 
 constant, 
 
 even 
 
 if 
 
 the 
 
 motion 
 
 is 
 
 multi-dimensional. 
 {info}

h5. Learning Objectives

Students will be assumed to understand this model who can:

* Explain the difference between how physicists use the term [acceleration] versus the everyday use of the terms "accelerate" and "decelerate".
* Describe the features of a [motion diagram] representing an object moving with constant [acceleration].
* Summarize the givens needed to solve a problem involving motion with constant [acceleration].
* Construct a consistent sign convention for the initial velocity, the final velocity and the acceleration in the case of objects that are speeding up or slowing down.
* Describe the features of a [position versus time graph] representing an object moving with constant [acceleration].
* Given a [position versus time graph], determine whether the object represented is speeding up or slowing down.
* Given a linear [velocity versus time graph], determine the corresponding [acceleration].
* State the equation that relates [position], initial [velocity], [acceleration] and time for motion with constant [acceleration].
* State the equation that relates [position], initial [velocity], final [velocity] and [acceleration] for motion with constant [acceleration].
* Solve a quadratic equation for time.
* Mathematically solve for the meeting time and location of two objects moving with constant [acceleration] by setting up and solving a system of equations.
* Graphically locate the meeting point of two objects moving with constant [acceleration].
* Describe the trajectory of a [projectile].
* Describe the acceleration of a [projectile] throughout its trajectory.
* State the conditions on the [velocity] and [acceleration] that describe the maximum height of a [projectile].


h4. S.I.M. Structure of the Model


h5. Compatible Systems

A single [point particle|point particle], or a [system] such as a single [rigid body] or a grouping of many bodies that is _treated_ as a [point particle] with [position] specified by the system's [center of mass]. 

h5. Relevant Interactions

Some constant net [external force] must be present to cause motion with a constant [acceleration].

h4. Laws of Change

h5. Mathematical Representations

This model has several mathematical realizations that involve different combinations of the variables for position, velocity, and acceleration.
\\
{latex}
Learning Objectives
Students will be assumed to understand this model who can:
S.I.M. Structure of the Model
Compatible Systems
A single point particle, or a system such as a single rigid body or a grouping of many bodies that is treated as a point particle with position specified by the system's center of mass. 
Relevant Interactions
Some constant net external force must be present to cause motion with a constant acceleration.
Laws of Change
Mathematical Representations
This model has several mathematical realizations that involve different combinations of the variables for position, velocity, and acceleration. 
 Latex
\begin{large}\[v(t) =v_{
\rm 
i}+ a (t - t_{
\rm 
i})\]\end{large}
{

 Latex
}\\
{latex}\
\begin{large}\[x(t) = x_{
\rm 
i}+\frac{1}{2}(v_{
\rm 
f}+v_{
\rm 
i})(t - t_{
\rm 
i})\]\end{large}
{

 Latex
}\\
{latex}\
\begin{large}\[ x(t) = x_{
\rm 
i}+v_{
\rm 
i}(t-t_{
\rm 
i})+ \frac{1}{2}a(t-t_{
\rm 
i})^{2}\]\end{large}
{latex}
{note}In the above expressions, t{~}i~ is the initial time, the time as which the position and velocity equal x{~}i~ and v{~}i~ respectively. Often t{~}i{~}is taken to equal 0, in which case these expressions simplify.{note}
{latex}
 Note
In the above expressions, ti is the initial time, the time as which the position and velocity equal xi and vi respectively. Often tiis taken to equal 0, in which case these expressions simplify.
 Latex
\begin{large}\[v^{2}(x)= v_{
\rm 
i}^{2}+ 2 a (x - x_{
\rm 
i})\]\end{large}
{latex}
{note}This is an important expression, because time is eliminated.{note}

h5. Diagrammatic Representations

* [motion diagram]
* [position versus time graph]
* [velocity versus time graph]

|[!images^MathematicaPlayer.png!|^ConstAccel.nbp]|[Click here|^ConstAccel.nbp] for a _Mathematica Player_ application illustrating these representations using _phase_.|

|[!images^download_now.gif!|http://www.wolfram.com/products/player/download.cgi]|[Click here|http://www.woldfram.com/products/player/download.cgi] to download the (free) _Mathematica Player_ from [Wolfram Research|http://www.wolfram.com]|

h4. Relevant Examples


h6. {toggle-cloak:id=oned}Examples Involving Purely One-Dimensional Motion

{cloak:id=oned}
{contentbylabel:
 Note
This is an important expression, because time is eliminated.
Diagrammatic Representations
Image Added
Click here for a Mathematica Player application illustrating these representations.
Image Added
Click here to download the (free) Mathematica Player from Wolfram Research
Relevant Examples
 
 Toggle Cloak
idoned
Examples Involving Purely One-Dimensional Motion
 
 Cloak
idoned
falsetruetrueAND501d_motion,constant_acceleration,example_problem
|showSpace=false|showLabels=true|excerpt=true|operator=AND|maxResults=50}
{cloak}

h6. {
 Toggle Cloak
:
id
=
freefall
}
Examples 
 
 Involving 
 
 Freefall


{
 Cloak
:
id
=freefall}
{contentbylabel:
freefall
falsetruetrueAND50freefall,example_problem
|showSpace=false|showLabels=true|excerpt=true|operator=AND|maxResults=50}
{cloak}

h6. {
 Toggle Cloak
:
id
=
catchup
}
Examples 
 
 Involving 
 
 Determining 
 
 when 
 
 Two 
 
 Objects 
 
 Meet


{
 Cloak
:
id
=catchup}
{contentbylabel:
catchup
falsetruetrueAND50catch-up,constant_acceleration,example_problem
|showSpace=false|showLabels=true|excerpt=true|operator=AND|maxResults=50}
{cloak}

h6. {
 Toggle Cloak
:
id
=
all
}
All 
 
 Examples 
 
 Using 
 
 this 
 
 Model


{
 Cloak
:
id
=all}
{contentbylabel:
all
falsetruetrueAND50constant_acceleration,example_problem
|showSpace=false|showLabels=true|excerpt=true|operator=AND|maxResults=50}
{cloak}
{td}
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!carrier.jpg!\\
\\ !bball.jpg|width=235!
Photos courtesy [US Navy|
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Image Added

 Image Added
 Photos courtesy US Navy by:
 Cmdr. Jane Campbell
 Mass Communication Specialist 1st Class Emmitt J. Hawks
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