A sphere with a radius of 300, attached by the middle to the end of a segment of length 300, "runs" on the cylinder (from which the segment goes), although it should not. Why?

Question

AutoCAD

I made a cylinder and from it a segment 300 long. then, to the end of this segment, he attached a sphere (behind the middle). the sphere has a radius of 300. however, the sphere goes over the cylinder. although it shouldn't. why is this happening? I am attaching screenshots (they show the problem and the properties of the segment and sphere). I am also attaching my own work.

https://ru.files.fm/u/92pgpxu7#_