The applet canvas is divided into four sections. The top section illustrates
the concept of uniform circular motion as discussed in Section 5.1. The
animation on the left shows the position and velocity vectors of an object
in uniform circular motion. Note that like the position vector, the velocity
has a constant magnitude and continually changes direction. This similarity
is illustrated in the middle animation. The middle animation is there only
to illustrate this similarity; it does not show the actual velocity of the
rotating object. The velocity of the rotating object is tangential, not
radial. The last animation shows the acceleration (centripetal) of the rotating
The second section is an animation of an object rolling without slipping.
It shows the velocity and the position vector of a point on the rim
relative to the center of rotation. Relationships between the linear quantities
and their rotational counterparts are discussed in Sections 5.1 and 9.1.
The third section shows the overall velocity vector of a point on the rim
of the rolling body. The white vector represents the velocity of the center
with respect to the ground, and the red vector represents the velocity of
the point with respect to the center. The sum of these two vectors is the
cyan (blue) vector. It represents the velocity of the point relative to the
The fourth section draws the trajectory followed by a point on the rim.