Parabola Construction on a Sphere by Steve Phelps

Parabola Construction on a Sphere by Steve Phelps
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2014-07-02 05:27
In collections Spherical Geometry Ideas
This example demonstrates how to construct a parabola on a spherical surface, illustrating the concept of parabolas in non-Euclidean geometry. Key math concepts include spherical geometry, parabola definition (focus-directrix distance), and geometric constructions. GeoGebra commands used are Sphere, PointIn, Plane, IntersectPath, Point, Midpoint, Line, OrthogonalLine, and Intersect. Suitable for high school and above students to explore the intersection of spatial geometry and analytical geometry.

GeoGebra Commands & Parameters

  1. Sphere((0, 0, 0), 1) → a
  2. PointIn(a) → A
  3. PointIn(a) → B
  4. Plane(A, D, B) → c
  5. IntersectPath(c, a) → g
  6. PointIn(a) → C
  7. Point(g) → E
  8. Plane(C, D, E) → b
  9. IntersectPath(b, a) → d
  10. Midpoint(C, E) → F
  11. Line(D, F) → e
  12. OrthogonalLine(D, b) → f
  13. Plane(f, e) → h
  14. IntersectPath(h, a) → k
  15. OrthogonalLine(D, h) → i
  16. OrthogonalLine(D, c) → j
  17. Plane(E, j) → l
  18. IntersectPath(l, a) → p
  19. Intersect(p, k, 2) → G

AI Drawing Prompt Reference

Construct a parabola on a sphere. Start by creating a unit sphere, then select three points A, B, and C on the sphere to form plane c, which intersects the sphere to create path g. Next, choose point D on the sphere and use D and point E on g to form plane b, which intersects the sphere to create path d. Find the midpoint F of C and E, then use D and F to create line e. Construct a line f perpendicular to b through D, then create plane h using f and e, which intersects the sphere to create path k. Next, create a line i perpendicular to h through D, and a line j perpendicular to c through D. Use E and j to form plane l, which intersects the sphere to create path p. Finally, find the intersection point G of p and k.
The prompt above was compiled from the original drawing commands and is for reference only.