The behavior of powder when compressing a cube with an open top varies significantly based on the type of powder and its packing density. Frictionless powders may flow more easily than liquids, while powders like chalk could form mounds instead of flowing continuously. The rate of compression also affects the outcome; slow compression might lead to settling and a lower surface level, while rapid compression could result in the powder being expelled. Tightly packed powders may bulge or squirt out depending on the speed of compression. Conducting an experiment with various powders in a plastic container is suggested for practical understanding.
#1
chemart
6
0
If I have cube with top side opened with powder in it an i start pushing two sides of cube together will powder fall out of cube the same as with water or other liquid?
It depends what kind of powder. If you had a frictionless powder, then it would flow even better than water. If you had chalk powder or something like that, then it would probably form a larger mound and not flow continuously.
This is only an educated guess, though. I have never tried this experiment!
#3
Danger
Gold Member
9,793
251
It would also depend to some extent upon how tightly it's packed in the first place, along with how forcefully and quickly you compress the box.
If it's just poured in loosely, there'll be a lot of air spaces. In that case, slow compression might actually lower the surface level as the material settles into a more compact arrangement. Conversely, a rapid compression could cause the air to blow the stuff out.
If it's been tamped down so as to leave little air space, a slow compression would probably cause a bulge on top as DH said, but a fast squeeze might 'squirt' it out.
Why don't you get yourself a plastic box (like Gladware or similar) and some different types of powder. Experiment, already!
Do we even know? My understanding of dark energy is that particles come into existence, exert and outward force, then vanish. My problem with that is how, of course, then how does dark energy know to push everything in the same direction? The pressure exerted would be in all directions, even if the space was moving so why isn't stuff pushed all over the sky?
Thanks - rev