2006-08-16 23:48:59 · 17 answers · asked by Sweetie 2 in Entertainment & Music ➔ Other - Entertainment
It's a question of what is known as "displacement". The amount of water a ship displaces weighs more than the ship itself. In the case of the needle, the needle weighs more than the displaced water. Picture putting the ship in giant bathtub filled dead level with water. As the ship settles in the tub, the water overflows. If you weigh this overflow water, it will weigh more than the ship. Since the ship weighs less it floats. If you repeat this experiment with the needle, the results will be the opposite - the needle will weigh more than its overflowed water, and so it sinks.
2006-08-17 00:00:21 · answer #1 · answered by Anonymous · 1⤊ 0⤋
It has to do with the surface area of the object and water displacement. As an object enters the water it presses down on the water and displaces it (removes it from under the object). The water pushes back on the object trying to return to its original spot. If the weight of the water which the object displaces is greater than the weight of the object, the pressure of the water is then sufficient to support the lesser weight of the object. This is called buoyancy. A ship is designed to meet the above criteria for buoyancy, a needlee does not because its surface area and weight displaces less water than the weight of the needl itself. Make sense?
2006-08-17 07:20:14 · answer #2 · answered by Anonymous · 0⤊ 0⤋
a needle sinks only if you break the "skin" on top. Place a needle carefully onto the surface of the water and it will float. Anyway, a ship floats because of the way it is bulit
2006-08-17 06:54:46 · answer #3 · answered by tombraider 3 · 1⤊ 0⤋
The needle is denser than the ship.
Remember, when talking about density, you need to take the whole object into account, meaning the ship, and the air inside it. When the ship fills with water, it sinks.
2006-08-17 06:53:17 · answer #4 · answered by 006 6 · 2⤊ 0⤋
water has water tension and since needle is small... long and very slim... and... denser than water.... it breaks the water tension and sink.
A ship however is different. it has a larger surface area at the bottom which holds it up the surface of the water. the "curve" shape of the boat also helps make it "less dense" incomparison to water (air filled in the curve) and therefore... ships float. =)
2006-08-17 06:57:22 · answer #5 · answered by Spidergurl 4 · 0⤊ 0⤋
Along with density, displacement of water is what helps things float. Since water applies pressure against an object as the water gets displaced, if the object displaces enough water the pressure from the water in essence holds the object up.
2006-08-17 06:57:48 · answer #6 · answered by Billy 4 · 0⤊ 0⤋
The needle is denser than the ship.
always remember, the thing having less density will flow on water. eg wood. and the density of needle is egual to the density of iron since it is made up of iron and the density of iron is much more as compare to water so it will sink in water.
2006-08-17 07:04:46 · answer #7 · answered by Anonymous · 0⤊ 0⤋
Refer to Archemedes' principle. An object will float when weight of fluid displaced is more than the weight of the object.
2006-08-17 07:07:14 · answer #8 · answered by Geepee 5 · 0⤊ 0⤋
Buoyancy... It's a scientific law... By the way, ships sink, too...!
2006-08-17 06:54:28 · answer #9 · answered by KnowhereMan 6 · 2⤊ 0⤋
because of the density,the needle is solid, but the ship is hollow.
2006-08-17 06:53:11 · answer #10 · answered by bobbee 2 · 2⤊ 0⤋