Moving a Circle in a Parabola

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This Demonstration shows that the center of a unit circle tangent to the parabola
is at (0, 5/4). In addition, the segment connecting the point
and the tangent point
makes a 60° angle with the vertical axes of the parabola.
Contributed by: Abraham Gadalla (July 2011)
Open content licensed under CC BY-NC-SA
Snapshots
Details
Checking the "answer" checkbox gives the radius of the purple circle. When the circles are tangent, the values of the radii are 1, 2, 3, 4, ….
Checking the "ice cream" checkbox shows the three tangent spheres and the ratio of their volumes to the volume of the paraboloid obtained by revolving about the
axis.
Reference
[1] J. Stewart, Calculus: Early Transcendentals, 5th ed., Belmont, CA: Brooks/Cole, 2007, Chapter 3.
Permanent Citation