Circle & Ellipse Intersection: Can you Make Them Touch?

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A circle and an ellipse with a focus at the circle's center can only touch at the ends of the ellipse's longer axis, which relates to the tangency condition. This means that if they intersect, the point of contact must be at this specific location. The discussion clarifies that varying the size of the circle does not change this constraint on tangency. The context of the question initially linked to elliptical orbits was acknowledged as more mathematical in nature. Understanding the geometric relationship between the two shapes is essential for grasping the concept of their intersection.
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What does it mean when one says that "A circle and an ellipse with a focus at the circle’s
center can touch each other only at the longer axis"?
Can't you, by varying the size of the circle, make it intersect the ellipse in a variety of ways?

Thanks! :)
 
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mps said:
What does it mean when one says that "A circle and an ellipse with a focus at the circle’s
center can touch each other only at the longer axis"?
Can't you, by varying the size of the circle, make it intersect the ellipse in a variety of ways?

Thanks! :)

Hello mps,
I assume the statement states constraint of the tangency condition.If they were to intersect the statement has no say.Do you seek a mathematical proof of this?If yes you have to show your attempt first.
regards
Yukoel
 
hi Yukoel,
no, i don't seek a mathematical proof. i just want to understand the statement. I still don't really understand... what do you mean by it "states constraint of the tangency condition"?
thanks for your help!
 
mps said:
hi Yukoel,
no, i don't seek a mathematical proof. i just want to understand the statement. I still don't really understand... what do you mean by it "states constraint of the tangency condition"?
thanks for your help!

Hello again!
If the circle and the ellipse touch or have a common tangent (two formulations of the same same statement) the point of contact has to be the end of longer axis of ellipse.I think this is what it means.
By the way this isn't related to physics I think so i think you have posted your query in the wrong section.
regards
Yukoel
 
Yukoel said:
... the point of contact has to be the end of longer axis of ellipse.I think this is what it means.
So you mean the end of the ellipse closer to the other focii?

Also I posted this here because it was in the context of elliptical orbits but now i realize it is more of a math question ;)
 
mps said:
So you mean the end of the ellipse closer to the other focii?

Yes.

regards
Yukoel
 
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