As young man I tried jumping down a steep dune ~100+ meters tall. My plan was to run, jump and roll all the way down. I got enough speed and air that I was about 2m up, which is high enough even at steep slope landing on sand to knock the wind out of you. And then I rolled, and bounced, and each bounce hurt. It was like whoosh, oww, bounce, owwww, bounce, owwww, etc. Also, sand in every orifice.
Moral victory: I probably lost 60m altitude rolling.
Re:What Makes Sand Soft?
by csunbird on Tuesday November 10, 2020 @05:28AM
(#25044420)
Also, when people think of sand, they think of beach sand, which is somewhat wet or recently was wet than it have dried, but there is also the variant of very, very dry sand (sometimes can be confused with earth), which is just a little bit softer than a solid ground.
Source: Someone who fell on deserts of Arabia, repeatedly, and almost broke a couple of bones.
Re:What Makes Sand Soft?
by batushka3 on Tuesday November 10, 2020 @07:41AM
(#25045312)
My best beach was Spiaggia di Is Arutas, Sardegna. It's a white pebble beach, grains arround half arborio rice size. Beach is soft to rest, umbrela still sticks well, wet or dry pebbles do not stick so your skin much. Just brush slighly and you're clean. Way better than sand.
Re:What Makes Sand Soft?
by frabert on Tuesday November 10, 2020 @09:07AM
(#25046040)
That kind of sand is quite common in (at least) all of the north-western beaches of Sardinia, due to the fact that they are mostly composed of granite and granite is very hard and does not break up easily, I guess.
Re:What Makes Sand Soft?
by leto_ii on Tuesday November 10, 2020 @04:48AM
(#25044220)
Still on the topic of sand, but more related to its dynamics than its softness, I would like to recommend the work of Per Bak [1].
Among other things he investigated and modeled the frequency and magnitude of avalanches in piles of sand, work that lead to the concept of self-organized criticality [2].
Re:What Makes Sand Soft?
by MaxBarraclough on Tuesday November 10, 2020 @02:23PM
(#25050388)
Sure, that's clearly the intent, but it's not what's written. What's written is that those industrial engineers who don't like sand, are also Anakin Skywalker.
As young man I tried jumping down a steep dune ~100+ meters tall. My plan was to run, jump and roll all the way down. I got enough speed and air that I was about 2m up, which is high enough even at steep slope landing on sand to knock the wind out of you. And then I rolled, and bounced, and each bounce hurt. It was like whoosh, oww, bounce, owwww, bounce, owwww, etc. Also, sand in every orifice.
Moral victory: I probably lost 60m altitude rolling.
Source: Someone who fell on deserts of Arabia, repeatedly, and almost broke a couple of bones.
https://en.wikipedia.org/wiki/Pyrrhic_victory
Among other things he investigated and modeled the frequency and magnitude of avalanches in piles of sand, work that lead to the concept of self-organized criticality [2].
[1] https://en.wikipedia.org/wiki/Per_Bak
[2] https://en.wikipedia.org/wiki/Self-organized_criticality
https://www.nytimes.com/2019/11/12/science/randall-munroe-mo...
[1] https://www.nytimes.com/column/good-question-randall-munroe-...
Some proper subset of industrial engineers don't like sand, and some proper subset of Anakin Skywalker doesn't like sand?
Venn diagrams aren't a good tool for expressing set equality.