Dr. Doe's Chemistry Quiz

A straw is essentially a cylinder — a continuous surface with a single tunnel through it. Topologically, this tunnel is considered one hole because:

A hole is defined as a continuous path that passes through an object without breaking it.

The opening at each end of a straw are not separate holes, but rather the two ends of the same hole — like a tunnel that starts at one side of a mountain and ends at the other.

If you imagine forming a straw by taking a flat sheet, rolling it into a cylinder, and connecting the ends, you’ve created one continuous passage — one hole. Consider a donut (torus). It has one hole — the hole through its middle. Now, if you stretch that donut into a straw shape, you haven't added any new holes; you’ve just changed its form. The topological nature remains: one continuous hole through the center. Despite having two visible openings, a straw has only one continuous hole — just like a tunnel has one hole with two ends, not two separate holes

Yes!