2007-02-15 22:20:10 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Engineering
Safety. Because it is impossible for a circular manhole cover to fall INTO a hole that is a little smaller than it. If you are lifting a square cover it is possible to turn it at an angle and drop it into the hole, possibly killing somebody down in the hole.
2007-02-15 22:25:25 · answer #1 · answered by Anonymous · 1⤊ 0⤋
because a man's (or woman's) body can be bent into nearly cylyndrical shape, the corners of a hole ar unnecessary. A circle gives the same effective size hole as does a square but with less area. thus there is a savings in material if manhole covers can be made round.
I find you question to be sexist. The modern and politically correct term is personhole.
2007-02-16 13:53:41 · answer #2 · answered by bignose68 4 · 1⤊ 0⤋
Because the diagonal distance of a square is bigger than its sides, That means that a square cover can pass through a square hole if passed through the diagonal. In a circle the diagonal distance(diameter) is constant.
2007-02-17 00:18:26 · answer #3 · answered by klomtrix 2 · 1⤊ 0⤋
its easier to drill a round hole in the ground than it is to drill a square ones........
2007-02-16 06:31:01 · answer #4 · answered by jdog44442003 3 · 1⤊ 0⤋
Because the hole is circular!!!
2007-02-16 09:52:23 · answer #5 · answered by Steven314159 2 · 0⤊ 0⤋