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The following hierarchical list has been developed and organized with several goals in mind:
* Each model must apply (approximately) to many situations in the world
* The models should cover mechanics as completely as possible
* The models should be ranked hierarchically with most general on top
* Each model should have a descriptive name and be accompanied by its most frequently used formula 

Even these requirements create some difficulties.  Firstly, we have to add a model for general energy conservation including thermal energy, even though this is usually considered part of Thermodynamics; Mechanics uses only the special case of Mechanical Energy, treating heat as "Lost Mechanical Energy".  Arranging the many models into a hierarchy with only four principle models (Kinematics, Energy, Momentum, and Angular Momentum) properly stresses that there are only a few basic models in Mechanics and that many of the most used ones are simply special cases of these few; however it obscures the logical chain of proof and derivation of the laws of mechanics from only F=ma and the definitions of kinematics.  (This usually starts with F=ma for point particles, then builds up and out to rigid bodies, systems of particles, momentum, angular momentum and energy.)  A further critique concerns the equations we associate with each model.  It is a simple operation of calculus to express the laws of physics in either differential (v = dx/dt, Σ{*}F* = m d{^}2{^}{*}x*/dt{^}2^ , Σ{*}T* = I *a*), or integral form (E{^}final^ = E{^}initial^ + W{^}nonConservative^ ).  By presenting only the most frequently used form, we obscure this simplification for the benefit of helping students link titles and verbal concepts to equations. 

h3. Hierarchy of Mechanics Models

[3D Motion General
* 2D Motion Genreal|3D motion (general)]

[2D Motion General |2D motion (general)]
** [Circular Motion |Circular Motion]
*** [Circular Motion with Constant Speed |Circular Motion with Constant Speed ]
{latex} $ (\alpha = 0) $ {latex}
** 1D Motion General
*** [1D Motion with Constant Acceleration]
**** [1D Motion with Constant Velocity]
{latex} $ (a = 0) $  {latex}
* [Simple Harmonic Motion]
{latex}  $ (a = -\omega^2 x) $ {latex}\\

 Energy, Work and Heat
* Work-Energy Theorem
{latex} $ (Q = 0, \Delta U_ {int} = 0)$ {latex}
*  [Mechanical Energy and Non-Conservative Work]
{latex} $(Q = 0, \Delta U_{int} = 0)$ {latex}
** [System Mechanical Energy Constant]
{latex} $ (W^{nonConservative}= 0 ) $ {latex}

[Momentum and Force]
{latex} $ \vec p(t^{final}) - \vec p(t^{initial}) = \int_ {t^{initial}}^{t^{final}}\sum\vec F^{ext} $ {latex}
* System Momentum Constant
{latex} $ (\sum \vec F^{ext} = 0 ) $ {latex}
* [Point Particle Dynamics]
{latex} $ (\sum\vec F = m \vec a ) $ {latex}

[Angular Momentum and Torque]
 
{latex} $ \vec L(t^{final}) - \vec L(t^{initial}) = \int_{t^{initial}}^{t^{final}} \sum\vec{\tau_o}^{ext} $ {latex}\\
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* System Angular Momentum Constant
{latex} $ (\sum\vec\tau_o^{ext} = 0 ) $ {latex}
* [Fixed-Axis Rotation |Fixed-Axis Rotation]
**  Statics 
{latex} $ (\sum \vec F^{ext} = 0 ) ${latex}
  and 
{latex} $ (\sum\vec{\tau_o^{ext}} = 0 ) ${latex}

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