A tube is cylinder with a hole all the way through, even paper ones.
Even square tubes?
The material on object is made from does not define the shape.
Very true, but a sheet of paper is easy to work with, and can conceivably be used as a plane rather than a 3d object. So yes paper or jelly all the same in practice but as a thought exercise ones easier.
A 2D shape needs to be able to lay flat on a level surface
No, it needs to have no volume.
If a plane of jelly is planar, if i roll it into a tube, its still planar, viewed from its end you'd not see it as it has no physical presence in the 3rd dimension. Its flat.
Even square tubes?
That would be a square.
If a plane of jelly is planar, if i roll it into a tube, its still planar, viewed from its end you’d not see it as it has no physical presence in the 3rd dimension. Its flat.
You're digging a big hole for yourself.
That would be a square.
Not a cuboid?
Doh!
The hole in the cup stops before going all the way through.
If that was the body work of your car you'd call it a dent not a hole...
A paper cup has no holes apparently.
Nothing to with it being paper per se. One of the cones hasn't got a hole in it in conceptual terms its a two planes, inside and outside. One with a flat bottom is 3d as it has 4 planar surfaces. It consists of 2 2d* shapes (or more in most cases) added together.
Edit - if I'm genuinely wrong...
A 2D shape needs to be able to lay flat on a level surface
What is the triangle i suggested you draw on a sheet then roll up once you've rolled it? I completely accept that in orded to actually exist in a way we can perceive as a physical object a straw has to have wall thickness so isn't a theoretical planar construct but as i say it's a thought exercise.
A real straw has a single hole if that's the word you want to use.
If that was the body work of your car you’d call it a dent not a hole…
I've never managed to get much tea in a dent.
I’ve never managed to get much tea in a dent.
You get sod all in a mug either in my office.
Thirty spokes are joined together in a wheel,
but it is the center hole
that allows the wheel to function.
We mold clay into a pot,
but it is the emptiness inside
that makes the vessel useful.
We fashion wood for a house,
but it is the emptiness inside
that makes it livable.
We work with the substantial,
but the emptiness is what we use.
A real straw has a single hole if that’s the word you want to use.
Fake straws! Are you trump.
Just a toady
Edit oh so's he
