/sci/ - Science & Math

so it doesn't fall down the hole.

A manhole cover is round, because it isn't a square.

>>2164837
because the hole is round, duh

Because manhole is round. They are not round for manholes of other shapes.

if it's square, the corners wear down really fast.
with round covers there are no corners and so
you dont have to replace them as often.

# Because the hole is round
# Because animals dig round holes, so it feels natural to humans too
# Because a circle offsets the straight lines of a city
# Because it is easier to roll the cover some distance than carry it
# Because it won't fall into the hole - but, the same is true for an equilateral triangle
# Because it is easier to pour hot metal into a circular mold than one with sharp corners

because OP is a faggot

Drilling round holes is easy
Drilling square holes is very difficult

therefore, the manhole, which is drilled from the top to an underground sewer/pipe is round and the cover is round as well.

>>2164879
>implying manholes are drilled

so that way no trolls can pick it up and drop it down the sewer, rather than with square when you can drop it diagnally and it'll fall down

A man hole is round because a circle is the only shape that circular hole is covered with a circular lid it is impossible for the lid to fall into the hole.

>>2164892
Couldn't any shape with congruent sides satisfy this requirement?

>>2164899
try to shove a cap to a bottle into the bottle without warping the cap

>>2164905
Yeah I understand that, but I'm also having a hard time imagining how I could do the same with something like a cap with a square for a side. I dunno what to call the three dimensional shape.

>>2164917
>draw it in paint
>post here
>???
>profit!

>>2164889
>implying they aren't

>>2164899

No. For all shapes excepting circle, there is some maximum diameter > minimum diameter. Cover can be lifted, rotated about minimum diameter so that axis is parallel to plane of frame surrounding hole, then rotated so that minimum diameter of cover aligns with maximum diameter of frame. Then drop into hole.

For circle maximum diameter = minimum diameter; no drop into hole.

It's obviously because manholes are round. Why are manholes round? Because the circular shape is the strongest shape to resist the compression of the earth surrounding it.

>>2164952
triangles work. this faggot was onto something... >>2164866

You're being interviewed for a position with Microsoft right now aren't you?

Answer: If it were any other shape it could fit through the hole it covers and fall in when turned to an angle.

>>2164953
>resist the compression of the earth surrounding it.

retard, you just went full nigger.

because people are shaped circle when we're climb ladders

>>2165016
A derp has herped, 1 cm = 0.01 m

Here's something

http://www.google.ee/images?q=manhole square

>>2164965
this

>>2165016
>.01cm thick manhole
whatthefuckamireading.jpg

>>2165019

Estonia, huh?