It is impossible to drop a round lid into a smaller round hole.
It is because round is the only shape that if turned or flipped over, it still retains the same length across its center. If you used a square, rectangle, triangle, hexagon or any other shaped lid, it could be rotated and fall into the hole.
This can't happen with the round shape.
And I have worked for the phone company for the last 22 years, yes it is a pain to get a rectangular lid that weighs 100 lbs, out of a 6 foot deep hole by yourself.Two more correct answersA round cover can be moved by rolling it on its edge.
A round cover contains less metal than a same-sized cover of any other shape.
actually a round manhole cover isint the only shape that would work a reulux triangle would work too and square manholes would puncture tires
A round manhole cover will not fall through the hole, A square one will.
"Manhole covers" are simply spelled "manhole covers". The reason most of them are perfectly round is that a round cover cannot slip down into a hole that is even just slightly smaller than the cover (as can oblongs or squares).
You can lift up and roll the manhole cover away. It will not fall into the hole.
A square one would fall through itself but with a round one this is impossible
Manhole covers are round because that is the only shape that will not fall in on itself. Having a round cover with a lip, there is no way the cover can fall or be forced into the hole it covers.
The round manhole cannot fall into the hole no matter which way you turn it.
Round manhole covers are generally used over square manholes because they cannot fall through the manhole openings. There is a chance that if square manhole covers are used they can be turned at an angle and fall through the manhole opening. Round manhole covers can be moved more easily as well.
Yes it will give
Rim, on a manhole, is the elevation of the top of the cover on the manhole. In a roadway the rim will at be final grade, in grass they can be sumped, flush or stick up.
A manhole weighs nothing...it's a hole. It's the cover that weighs about 100 pounds.
1) That way, they can easily be moved, by rolling them. 2) They can't accidentally fall into the manhole.
Around 100 pounds.
with a crowbar =] or brolic hands =]
because for any person to get inside a manhole, you would think it was shaped like a round circle.
he was sommitting cewercide
A manhole cover is circular so that one person can roll it away from the hole it covers without running the risk of it falling into the hole.
Impossible to answer ! There is no 'register' of the location for every single manhole cover. Additionally, there could be many thousands on private properties.
A circular cover is the only shape that can fit the hole no matter which way you drop it, but can't possibly fall through the hole no matter which way you drop it.
The reason that manhole covers are round, and not square, is because a square cover could, when placed at the right angle, fall through the square hole in the ground. A circle, however, is the same diameter no matter where you measure it, and it cannot fir through a hole the same size and shape, no matter how hard anyone tried.
A Man Hole Cover is the grid/grill that goes over a sewer hole or drain in the streets.
becaus no mater witch way you turn the lid it stil fits in.
It's so it never falls in the hole. The radius of the manhole cover is greater than the radius of the manhole. Therefore, it can never fall in. Any other shape (square, triangle, decagon, etc.) can fall in if manuvered to the correct angle. It's so it never falls in the hole. The radius of the manhole cover is greater than the radius of the manhole. Therefore, it can never fall in. Any other shape (square, triangle, decagon, etc.) can fall in if manuvered to the correct angle.
Man hole covers are round so that the cover cant fall into the hole no matter what angle it is oriented at as the diameter is equal around the entirety of the circle. This would also work for an equilateral triangle but it would make it less comfortable when climbing in.