• sygnius@lemmy.world
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    7 months ago

    There’s a risk that if you try to turn the square cover that the cover will fall into the hole. It’s really strange that it’s square and not round.

    • Hyperreality@kbin.social
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      7 months ago

      It’s really strange that it’s square and not round.

      It’s not even slightly strange. These are incredibly common all across Europe and the world.

      It’s a small cover, almost certainly to service the nearby drainpipe or perhaps for the water or gas connection to a house.

      The chance of it falling in the hole is zero unless you’re trying to do it on purpose. Lift and slide, done.

      And even if it does fall in, you can simply reach in and pull it out.

    • ZephrC@lemm.ee
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      7 months ago

      I’m pretty sure the reason is that the hole isn’t deep enough for it to matter. That’s nowhere near big enough to be a manhole.

      • blargerer@kbin.social
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        7 months ago

        Yes it is. In any rectangle, by definition the diagonal cross section will always be longer than the longest side. Therefore given that this is a relatively 2d shape in 3 dimensional space, it will be able to pass through the hole.

        • Hyperreality@kbin.social
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          7 months ago

          Depends. The cover is resting on the inside lip which prevents moisture getting in. Ie. this cover is actually significantly bigger than the hole it’s covering.

          Eg. if this cover is 25x25, but it’s covering a hole which is less than 18x18 (c=25.5), it’ll be quite hard to drop the cover in.

        • Possibly linux
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          7 months ago

          The problem is the hole is smaller than the cover. If they were the same size it would fall though

          • sygnius@lemmy.world
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            7 months ago

            I think you’re misunderstanding. Yes, it cannot fit in when it’s angled properly to fit into the hole. However, if you angle the plate 45 degrees and lift one end of the plate, it will fall into the diagonally. That’s why manholes are round shaped. There is no angle for a round cover to fall into the hole itself.

            • Possibly linux
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              7 months ago

              You are right, never mind. I was thinking Pythagorean theorem