Example · High school
Terms
| Term | This example | Why |
|---|
| sphere |
✓ |
|
| sphere topological |
✓ |
The surface of a basketball is a sphere, and so a topological sphere, because it consists of the points at one distance from the center.
|
| connected |
✓ |
The surface of a basketball is connected because it is path-connected.
|
| path connected |
✓ |
The surface of a basketball is path-connected because every two points are joined by an arc of a great circle.
|
| simply connected |
✓ |
Although it is hollow, every loop on it can slide off to a point.
|
| ball |
✗ |
The surface of a basketball is not a ball, because it does not include the inside.
|
| open ball |
✗ |
|
| closed ball |
✗ |
|
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