The Conic Sections as the Locus of Perpendicular Bisectors
The blue lines represent the locus of perpendicular bisectors between the point Focus and all points on the circle. The envelope of this locus forms a conic section.
What is the shape of the conic when Focus is outside the circle?
What is the shape when Focus is inside the circle?
What is the shape when Focus and the Center are coincident?
You can use the Show Bisector button to display a single bisector between Focus and a point on the circle. (Drag this point around the circle to sweep out the entire locus.)
How could you construct only the envelope of the conic? How might you compute the eccentricity?