why is manhole round?
143766
Simple!  A manhole is round so that the cover can never fall in.  If it were any other shape, like a square, rectangle or oval, you could take the cover out, flip it sideways and drop it in, but with a round hole and a round cover, it will always be just a little too big.\n\nPart 2:  I would still call it a hole if it was square.  Why wouldn't you?  Plenty of holes aren't round.  Button holes are very narrow compared to their length.  And I guess the Indian Government aren't concerned with people dropping manhole covers into a sewer, or didn't think about it.
788434
ist a holeeeee\n\nbut u kinda can take it out...well...cover it with cement anyway..so its technically not there anymore
656252
It is because the round or circular shape is the most uniform shape of all (there are no edges or corners) - this means the amount of stress force exerted from the surrounding soil is uniformly distributed onto it; wheareas if it was some other shape with corners or edges, then stress concentration would be higher at those places, which would cause cracks/erosion that can destroy the pothole.
657115
A circle is the strongest shape in the world. Thats why most bridged and tunnels have arc shaped ceilings. Eggs are not perfect ovals. one side is a wider angle than the other. This is to prevent the eggs from rolling off the nest or burrow or whatever.
821694
It's round because it has enough gravity to make it round, the force of gravity crushing away irregularities until a round shape is achieved. There's actually a limit in astronomy, anything with more mass then a certain amount will as a rule be round.\n\nAs for the holes, I assume you mean the craters. They are there because we're basically living in a shooting gallery of asteriods, comets, and meteors. On the moon there are no erosive forces so when one hits it the impact crater remains.
707768
good ques and i have a good answer like a ball it is round and not flat so gravity is pulling it and its making it rool...the edges are gettign pullled by gravity and then its rolled of the table and pulled strait down to the ground..
24402
Two or three more than the number of manhole covers.\nSorry.  Some estimate between 125,000 and 750,000 in the urban areas of the United States.\nBy the way, do we have to call them Peoplehole covers?
315756
It's crooked because it begins by growing horizontal to the bunch.  Gravity pulls it down.
349292
They are round because that shape can withstand the most amount of pressure without exploding/collapsing. The shape is also called a pressure vessel.
7958
It's kind of neat. Only a round cover will not fall through the hole it covers. Any other shape, if turned the wrong way can slip through the hole and fall.
287552
excitement causes it.\nits a lubricant\nyour lubricant porthole is set a little closer to your opening than normal.
1158378
It seems flat to me.  However, when I peer intently  at lines of clouds over a real-long horizon I detect a curl this way and that, like it's following some sort of curvature of the surface in a distant kind of way.  It's really spooky.  But you include the question "Was it ever round?"  So if you want more on the subject, listen to Phil Hendrie on xm radio channel 152, and sometimes he has a guest General Johnson Jameson, who attempts such inquiries.  As an added bonus, a few conversations about a society of small people who live in a magical land.
1089145
No, planets and stars are round because of gravity (to be more accurate, gravity is the curvature of space-time). This is a caused by a different phenomena than surface tension, which is due to the electromagnetic attraction between water molecules. The force of gravity and the electromagetic force are two different forces.  \n\nSurface tension does not actually make the drop round; air pressure does that.  Surface tension simply gives the drop an outer wall like the wall of a balloon.  \n\nThe reason that water drops form into spheres is the need to equalize the pressure inside the drop. Air pressure tries to squeeze the drop, and the internal pressure inside the drop pushes back  - creating the internal pressure of the drop. This puts tension on the wall of the drop (Where the wall of the drop is caused by surface tension.). The geometric shape of the sphere minimizes the wall tension (http://hyperphysics.phy-astr.gsu.edu/Hbase/surten2.html).  A shape with corners, such as a cube, would allow forces to be concentrated at the corner, which would smash the corner flat, or else cause the area around the corner to expand. A sphere allows for an even pressure distribution.\n\nThe pressure on a planet is caused by its own weight pulling its own matter inward.  A sphere allows for an even distribution of gravational 'pressure'.  \n\nIn other words, a sphere resists being crushed better than any other shape, so objects under internal or external pressure tend to become round (irregardless of what is causing the pressure).
12606
Our world, Earth, is a planet, and planets are round because their gravitational field acts as though it originates from the center of the body and pulls everything toward it. With its large body and internal heating from radioactive elements, a planet behaves like a fluid, and over long periods of time succumbs to the gravitational pull from its center of gravity. The only way to get all the mass as close to planet's center of gravity as possible is to form a sphere. The technical name for this process is "isostatic adjustment."\n\nIf the shape of the Earth were due solely to gravity it would be a perfect sphere (round in 3 dimensions) but it's not, the Earth is shaped like what is called an oblate spheroid. As the Earth spins on it's axis, it produces a centrifugal force that pulls away from the Earth (in opposition to gravity)  at 90 degrees from the spin axis, this corresponds to the equatorial regions. So the Earth bulges out a little around it's middle.
905734
Both are holes.  I don't think it comes from anywhere.  It's supposed to indicate that a person is stupid.  They don't know one hole from the other.
233363
Its actually not round, its more of an oval shape.
884879
Because the earth is round, and if you made your flat map a oval(circle), the oceans would connect and become one!