2007-10-31 13:05:48 · 18 answers · asked by Anonymous in Science & Mathematics ➔ Earth Sciences & Geology
Actually you can. When you dug up the dirt your loosen it. To get in back in the hole you need to compact it. Most surface soils are not especially well compacted when you dig it up for the first time.
In construction work, ditches, water lines, foundations,etc it is common to dig a trench, line it with sand, lay in the pipe or foundation and still get all the dirt back in. Soaking it with water will settle the dirt down to at least as compact as it was before it was disturbed.
If you walk around a a grave yard you will see fresh graves have mounds above the natural level but older graves are sunken. The mounds are ornamental, the sunken graves is what happens after a while (depending on climate) unless it back filled and leveled.l
2007-10-31 14:52:41 · answer #1 · answered by dougger 7 · 0⤊ 0⤋
The dirt you took out was compressed - all the air was squeezed out of it by a long time being walked on, rained on, etc.
Your shoveling mixed air into it, and you packing it down can't get the air out like a decade of traffic can do.
It doesn't fit back because air has come in between the particles, separating them.
2007-10-31 13:10:53 · answer #2 · answered by noname 7 · 1⤊ 0⤋
There are tiny spaces filled with air in soil. Eventually these spaces become smaller as the soil becomes more compacted. When you dig the soil up you are uncompacting it and introducing air back into the soil.
2007-10-31 13:10:18 · answer #3 · answered by cody s 2 · 3⤊ 0⤋
Maybe the dirt is now of a different texture & so won't be returned to the same hole in the ground. I'm an English major so this question is very hard for me. ;)
2007-10-31 13:09:15 · answer #4 · answered by jaksie3 2 · 2⤊ 2⤋
It was compacted. When you dig, you allow air in and it will not be as compacted should you try to re-fill the hole.
2007-10-31 13:08:44 · answer #5 · answered by Esther 7 · 3⤊ 0⤋
ok im guess ur tryin to kill time so ima kill some time and answer this question because of inertia and the 3 Laws of Motion that state Newton you see Newton is a very prologitic man who learned all this stuff trying to tell u so it has to do with inertia and compaction of Law 28 of Newtons 3 laws
2007-10-31 13:13:33 · answer #6 · answered by midsize D 1 · 0⤊ 0⤋
Compaction.
2007-10-31 13:08:37 · answer #7 · answered by Sarge 3 · 3⤊ 0⤋
Because when you dig it up, it is compact. To get it all back the same way, you have to press it down to compact it.
2007-10-31 13:08:52 · answer #8 · answered by Anonymous · 1⤊ 2⤋
the law of diminishing returns is in effect--you dont get all the fill dirt back
2007-10-31 13:08:46 · answer #9 · answered by Mike 7 · 1⤊ 2⤋
Air mixed in the dirt..........not as compact as what you dug out.
2007-10-31 13:09:15 · answer #10 · answered by marty 3 · 3⤊ 0⤋