Two openings, one cavity . If you think of it as a cylinder, it’s two holes. If you think of it as thick block with a perimeter marginally larger than the hole it only has one hole.
Does a straw have 2 holes or 1 Reddit?
“ An ideal straw has no holes . It is a pipe. “If it had a hole, it would leak,” mused one commenter. “A straw with a hole is a defect.”
Does a straw have two holes or one?
For a surface with boundary, such as a straw with its two boundary circles, each cut must begin and end on a boundary. So, according to Riemann, because a straw can be cut only once — from end to end — it has exactly one hole .
How many holes does a straw have quiz?
Straws have two holes .
How many holes are in pants?
A pair of pants is any surface that is homeomorphic to a sphere with three holes , which formally is the result of removing from the sphere three open disks with pairwise disjoint closures.
Does a toilet paper roll have 2 holes?
Simple answer is, a roll of toilet paper has 1 hole going through it , like an open cylinder. The hole through an open cylinder is end-cap to end-cap. It’s not a torus, though they have can have holes. Torus holes can also have a 0 radius, or even a negative radius, and it’s still considered the “hole”.
Do straws have 0 holes?
“ An ideal straw has no holes . It is a pipe. If it had a hole, it would leak.” “‘Technically’ a straw has one hole but ‘technically’ it does not.
Is a straw a hole?
The mathematically correct answer is 1 hole . A straw is topologically the product of a circle, which has 1 hole, and an interval, which has 0 holes. So the straw has 1 hole. ... Intuitively, we can agree a circle has 1 hole–the simple closed curve contains a 2-dimensional hole inside of it.
Why does a straw have zero holes?
Someone out there is going to try and tell us that if you wrap a straw and make the ends meet, you get a torus . It’s all contained, and therefore has zero holes. ... A torus of this type would look like a donut. So it would have at least one hole.
How many holes are in your brain?
Lobes of the brain
The cerebral hemispheres have distinct fissures, which divide the brain into lobes. Each hemisphere has 4 lobes : frontal, temporal, parietal, and occipital (Fig. 3). Each lobe may be divided, once again, into areas that serve very specific functions.
How many holes does a woman have in his body?
There are two openings in the vulva — the vaginal opening and the opening to the urethra (the hole you pee out of). The urethral opening is the tiny hole that you pee out of, located just below your clitoris. The vaginal opening is right below your urethral opening.
How many holes does a woman have in her Virginia?
Yes there are 3 holes in the vaginal area. As a background, the outside of the female genital area is called the vulva. The outer lips of the vulva are called the labia majora. The inner lips are called the labia minora.
How many holes does a paper towel roll have?
Twitter user Garratt Dennis agreed, writing: “Okay I could be wrong but I think a hollow cylinder (the paper towel roll) is homeomorphic to a torus which has one hole, therefore the roll of paper towels has one hole with two openings .”
Is an opening a hole?
A hole is an opening in something that goes right through it .
What makes a hole a hole?
A hole is an opening in or through a particular medium, usually a solid body . ... Depending on the material and the placement, a hole may be an indentation in a surface (such as a hole in the ground), or may pass completely through that surface (such as a hole created by a hole puncher in a piece of paper).
Does a bowl have a hole?
A bowl has no holes (genus 0), a coffee cup has one (through the handle – making it genus 1), a pair of spectacles (without the pieces of glass) has two holes (genus 2), and a pretzel can have three holes (genus 3).
