Why ice floats in water????can it be possible to needle float in water??

Question

...

Answer 1

#1 Anything floats in water because of a lower density.

#2 It appears that your using needle as a verb.

Answer 2

ice is less dense, and generally, there is air in ice...small but usually  there

Answer 3

Actually you can make a needle float on water.  What you need to do is take a rolling paper and set the needle on top of it.  Gently set the paper on the surface of a bowl of water.  As the paper fills up with water it will eventually sink and your needle will magically float on top of the water.  However you don't want to use your last rolling paper.  If you do that then ice floating on water won't inspire your inquisitive mind.

Answer 4

As mentioned, ice floats because it is less dense. A needle will not float IN water but you can float a small needle on TOP of the water. The surface tension of the water is enough to keep the needle from sinking, just like water bugs float on the surface tension. I know because I have done it.

Answer 5

We have two different, but related, things going on here. Ice floats in water. A small needle can "float" on water. The important difference here is between "in" and "on".

You can see the difference clearly if you put an ice cube in one bowl and a small needle in another bowl. Pour water in the bowls until they are almost full of water. The ice cube rises to the top of the water, but the small needle stays at the bottom of the bowl. The scientific concept involved here is called buoyancy, the upward force on a body immersed in a fluid (a liquid or gas). Now this buoyancy comes only from the part of the body that is in the fluid. If the buoyancy is greater than the weight of the object, the object moves upward. When some of the object is out of the fluid, then the buoyancy (upward force) is less. When just the right amount of the object is out of the fluid so that what remains immersed gives a buoyancy exactly equal to the weight, then the object is at rest, floating in the fluid with some of the object out of the fluid.

As a general rule, materials expand when their temperature increases and contract when their temperature decreases. This connected with buoyancy results in hot air rising, hot water rising, cold air sinking, and cold water sinking. But a very peculiar thing happens with water. When its temperature gets close to the freezing point, water starts expanding as the temperature decrease. Most liquids freeze from the bottom up, because the coldest liquid has contracted the most (become heaviest for the space it occupies) and sinks to the bottom. Because of the very peculiar behavior of water, cold water sinks until the temperature gets close to freezing, but then as the temperature decreases further, the water expands! And the colder water rises to the top! An unlike most liquids, water freezes from the top down. As a result, people walk on water (frozen into ice) on lakes in the winter and go ice fishing. All this is due to the peculiar behavior of water. Without this peculiarity, nobody could go ice fishing. In fact, there probably wouldn't be any fish. There probably wouldn't be any people. So your question about why ice floats is really deep. It is a question about why there are fish and why there are people.

Something like buoyancy is related to the needle floating on water. Here the scientific concept is surface tension. This is related to mutual attraction between the molecules making up a liquid. In simple terms, the surface of a liquid has a certain resistance to anything coming into the liquid. You might say that the surface wants to keep being the surface unbroken. So the needle presses down on the surface of the water, deforming the surface and making a small depression. That depression means a slight rise in the level of the surrounding water, resulting in an upward force exactly similar to buoyancy. Only we can't really call it buoyancy yet, because none of the needle has actually got "in" the water. The surface is still unbroken. This business of breaking the surface and getting "in" the water explains why the needle must be small (otherwise the weight would be enough to break through the surface), why the needle must be placed very carefully on the surface (otherwise the movement breaks the surface), and why the needle must be flat on the water surface (if you put it on the water point down, for example, then the weight of the needle concentrated on one point of the surface would be enough to break the surface). You can also reduce the surface tension of the water chemically, for instance, by adding a drop of liquid detergent to the water. If the needle was floating on the surface held up between the surface tension and you add some detergent to reduce the strength of the surface, then the needle breaks through the surface.

Answer 6

Ice floats due to it's structure which contains lots of air/empty space, leading ice to be less dense.

If you know about the Dead Sea, then you know that people can float in it because the salt concentration is so high that the water becomes more dense then usual.  So if you add enough salt, you could (it's a possibility) make the needle float.

Answer 7

Ice is less dense than water is, and no, a needle cannot float in water, but that's just common sense.