What is quicksand?

Answer 1

"Quicksand" is an ultimate in misnomers.

Its not sand.

Its essentially a mud pit.

Answer 2

Quicksand is a mixture of sand and water, or sand and air, that looks solid, but becomes unstable when disturbed by any additional stress. In normal sand, grains are packed tightly together to form a rigid mass, with about 25 to 30 percent of the space (voids) between the grains filled with air or water. Because many sand grains are elongate rather than spherical, loose packing of the grains can produce sand in which voids make up 30 to 70 percent of the mass. This arrangement is similar to a house of cards in that the space between the cards is significantly greater than the space occupied by the cards. The sand collapses, or becomes 'quick,' when additional force from loading, vibration or the upward migration of water overcomes the friction holding the grains together.

Most quicksand occurs in settings where there are natural springs, either at the base of alluvial fans (cone-shaped bodies of sand and gravel formed by rivers flowing from mountains), along riverbanks or on beaches at low tide. In such cases, the loose packing is maintained by the upward movement of water. Quicksand does occur in deserts, but only very rarely: where loosely packed sands occur, such as on the down-wind sides of dunes, the amount of sinking is limited to a few centimeters, because once the air in the voids is expelled the grains are too densely packed to allow further compaction..

Answer 3

Quicksand is basically just ordinary sand that has been so saturated with water that the friction between sand particles is reduced. The resulting sand is a mushy mixture of sand and water that can no longer support any weight.
Please see the web pages on how quicksand works.

Answer 4

Quicksand is a hydrocolloid gel consisting of fine granular matter (such as sand or silt), clay, and salt water. The origin of the name refers to "quick" in the older meaning of "alive" rather than "fast," and is thus similar to the origin of the term quicksilver for mercury.

When undisturbed it often appears to be solid, but a minor (less than 1%) change in the stress on the quicksand will cause a sudden decrease in its viscosity. After the initial perturbation—such as a person attempting to walk on it—the water and sand in the quicksand separate and dense regions of sand sediment form; it is because of the formation of these high volume fraction regions that the viscosity of the quicksand seems to suddenly increase. In order to move within the quicksand, a person or object must apply sufficient pressure on the compacted sand to re-introduce enough water to liquefy it. The forces required to do this are quite large: to remove a foot from quicksand at a speed of one centimeter per second would require the same amount of force as "that needed to lift a medium-sized car." [1]

It was commonly believed that the behavior of quicksand was due solely to saturated or supersaturated suspensions of granules in water. Pressure from underground sources of water would separate and suspend the granular particles, reducing the friction between them. As of September 2005, it has been shown that it is the presence of salt that is largely responsible.[1] The stability of the colloidal quicksand is compromised by the presence of salt, increasing the likelihood of sand flocculation and the formation of the high viscosity regions of sediment responsible for quicksand's "trapping" power.

Quicksand is not as dangerous as depicted in many movies. As quicksand is rarely more than a few feet deep, there is usually little danger of sinking below the surface. Even when the quicksand is deep enough, deliberate effort is required to sink below the surface. Quicksand is typically denser than the human body, meaning that a body is much more buoyant in quicksand than in water. Thus, the body will float quite easily in quicksand.

This was demonstrated in an episode of the TV series MythBusters and in an article in Nature. [1] The sand's higher density will gradually push a human body upward, eventually allowing one to paddle toward more solid footing. Typically the greatest danger of getting stuck in quicksand comes from exposure, starvation, flash flooding, or tidal flooding.

Quicksand can be found inland (on riverbanks, near lakes, or in marshes) or near the coast. It can also form when an earthquake increases groundwater pressure, forcing the water to the surface and causing soil liquefaction.

One region notorious for its quicksands is Morecambe Bay, England. As the bay is very broad and shallow, a person trapped by the quicksand would be exposed to the danger of the returning tide, which can come in rapidly.

Answer 5

quicksand is what which is called daldal in Hindi.
it is a mixture of sand and water,which on application of external force sucks the object into it.
which one usually sees like people going inside it.
in such a case a person on should lie down motionless.

Answer 6

It is very fine, powdery sand that has water flowing up from underneath it, causing objects to sink. However, killer quicksand that will suck a person under is a myth.

Answer 7

Quicksand is a hydrocolloid gel consisting of fine granular matter (such as sand or silt), clay, and salt water.

Answer 8

over a period of time sand will loosely arranged that is there will be more air space in between ,
factors influencing quick sand- water/moisture, wind, sunlight, and earth surface ,

Answer 9

In medical term? not sure.
In land terrian, its probably mud that looks like sand.

Answer 10

It sinking sand you stand in it and you sink down and suddenly your in your neck in it.