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krazzykalpana
krazzykalpana • Oct 5, 2008

Is flowing sand a 'fluid'?

hi
i just want to knw if sum1 asks u flowing sand is a fluid or not.wats d ans .justify.
raj87verma88
raj87verma88 • Oct 5, 2008
Re: question

Flowing sand is not a fluid. Think of a room filled to the top with balls. When you open the door all the balls roll out. Would you call it flowing and say that the balls are fluid. Its the same with sand. The particles are small tiny balls that roll over each other.
arpanmechengg
arpanmechengg • Nov 5, 2008
yes flowing send is flud u can say solid flude like a (Hg) mercury u knw i kn ur smart k bye
sriramchandrk
sriramchandrk • Nov 6, 2008
You can justify that flowing sand is not fluid with this sentence:
If you can stir it up with a spoon or blow it through a straw, it's a fluid.

More info on: What is a Fluid?

This was the simple explaination i could get through search.

Thanks & Regards
Sriram
raj87verma88
raj87verma88 • Nov 6, 2008
arpanmechengg
yes flowing send is flud u can say solid flude like a (Hg) mercury u knw i kn ur smart k bye
What in the world is a solid fluid? Mercury is a liquid at room temperature and so are caesium, francium, gallium and rubidium. There are 4 sates of matter gas, liquid, solid and plasma(at very high temperatures).
Gas and liquid are fluids.
I have already explained the concept of flowing sand not being a fluid using an example. I will give one more. Sand granules are irregular in shape. If you enlarge them a 1000 times, they may look like boulders or huge rocks. Now imagine a land slide, number of rocks of all shapes and sizes rolling down the mountain slope, rolling on top of each other. Will you call that flowing and say that the boulders/rocks are fluid?
By solid fluid, you may be meaning a gel like substance. If so then I think you are confusing Quicksand with Sand. Quicksand is a Colloidal Mixture of sand/silt, clay and salt water. It is a non-newtonian fluid. Looks like a solid if undisturbed. The other concepts are Dry Quicksand, Fetch Fetch etc. I have provided somelinks below.
Quicksand - Wikipedia, the free encyclopedia
Dry quicksand - Wikipedia, the free encyclopedia
Fech fech - Wikipedia, the free encyclopedia
Thixotropy - Wikipedia, the free encyclopedia
mshearer
mshearer • Nov 6, 2008
I doubt arpens post was a serious answer, instead a repsonse to the initial butchery of the english language provided by krazzykalpana
jackjp01
jackjp01 • Nov 6, 2008
Simple definition: A fluid is something that flows. I would definetly call flowing sand a fluid. The absolute viscosity would probably be very high. Here are a few more non-traditional examples of fluids:

- a rock slide (as mentioned before is like sand)
- a room full of balls when the door is opened
- car traffic (a classic example of a pipe flow problem)

If ya dont believe me then take your knowledge of fluid mechanics and apply it to the concept of the hour glass (using sand as the FLUID)
sgrshukla
sgrshukla • Feb 3, 2009
I think flowing sand is not fluid....because the basic property of the fluid is viscosity, though the sand layers flow over each other, it can't be said that it is having viscosity because viscosity is a function of temperature, if temperature increase viscosity decrease in real fluid, here it doesn't happen..so ultimately flowing sand is not fluid...
6nv6
6nv6 • Feb 4, 2009
no, because fluid includes gases and liquids only... sand is not either of them.. and sgrshukla is right about viscosity.. that called non-Newtonian fluid which can cause the viscosity to decrease, so the fluid appears "thinner"...
Abhijeet__
Abhijeet__ • Feb 6, 2009
Yes!
Sand is a fluid,it act's just as water and only its molecules are bigger and its viscocity is very heigh as compaired to water.
raj87verma88
raj87verma88 • Feb 6, 2009
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