**October 6, 1998**

**Added reference material... Kinematics Kit in Exploratories.**

**Motion Concepts (Note that D means delta or change)**

Position Along Path... x

Reference and initial position xo

**Velocity Tangent to Path... V**

**V = Dx/Dt............ Dx = V Dt**

**Acceleration... a**

**a = DV/Dt ..............DV = a Dt**

Along Path.... apath

**Changes magnitude of V**

**Perpendicular to Path.... aperp
**

**Changes direction of V**

How big is acceleration perpendicular to path?

Note that acceleration to path points toward the center of the curve (the direction of DV)

**If acceleration is not along path or perpendicular to
path, it must be "broken" into components, apath and aperp, by drawing
a rectangle with one side of rectangle along the velocity vector and the
acceleration vector is the diagonal of the rectangle. See two examples below...
the radius of curvature to the path of the particle is not shown.**

V, apath, aperp

**Describing Motion**

**Motion Diagrams . . .**

**Graphs...**

**Vectors...**

**Simulations**

**Interrelating descriptions**

**Constant Acceleration**