Without placing an object in water.how can you determine if it will float?

Answer 1

In physics, buoyancy is an upward force on an object immersed in a fluid (i.e., a liquid or a gas), enabling it to float or at least to appear lighter.
The buoyant force is equal to the weight of the displaced fluid.
If the weight of an object is less than the weight of the fluid the object would displace if it was fully submerged, then the object is less dense than the fluid and it floats at a level so it displaces the same weight of fluid as the weight of the object.

If the object has exactly the same density as the liquid, then it will stay still, neither sinking nor floating upwards, just as the liquid nearby stays still.

See buoyancy laws in
http://en.wikipedia.org/wiki/Buoyancy

Answer 2

The Larger the volume of an object the more chance of float an object as ship float due to Large volume but needle sinks due smaller volume

Answer 3

One may know if an object will float by knowing what is the composition of the object. Then one would need to calculate the density of H2O (water), which is 1 gram per a milliliter.

Refer to a table of Periodic Table to help you know the density of the object.

---- Also ----
Objects may also float on water if it can displace its weight on water. This is how giant ships float atop of water. Weight displacement.

Answer 4

"hello allapattah2005!
Things that float have less density than things that sink. To verify
this, an aluminum foil sheet (shaped as a boat ) can be placed in
an aquarium and be shown to float.
Destroy the boat by crumpling it up into a tight ball and then throwing it into the water. The aluminum now compressed into a ball will be observed sinking in
water. The major difference between the aluminum foil before compression vs. after compression was that the boat had more volumn than the compressed foil. The compressed foil had more mass than the boat shape.
Lets see, an object floats when water pushes up enough on the object to keep it from sinking. When an object pushes down harder than water pushes up, it sinks.

The standard definition of floating was first recorded by Archimedes and goes something like this: An object in a fluid experiences an upward force equal to the weight of the fluid displaced by the object.
So if a boat weighs 1,000 pounds (or kilograms), it will sink into the water until it has displaced 1,000 pounds (or kilograms) of water. Provided that the boat displaces 1,000 pounds of water before the whole thing is submerged, the boat floats.

How do the water molecules know when 1,000 pounds of them have gotten out of the way? It turns out that the actual act of floating has to do with pressure rather than weight. If you take a column of water 1 inch square and 1 foot tall, it weighs about 0.44 pounds depending on the temperature of the water (if you take a column of water 1 cm square by 1 meter tall, it weights about 100 grams). That means that a 1-foot-high column of water exerts 0.44 pounds per square inch (psi). Similarly, a 1-meter-high column of water exerts 9,800 pascals (Pa).

If you were to submerge the box 1 foot into the water, the gauge would read 0.44 psi (if you submerged it 1 meter, it would read 9,800 Pa). What this means is that the bottom of the box has an upward force being applied to it by that pressure. So if the box is 1 foot square and it is submerged 1 foot, the bottom of the box is being pushed up by a water pressure of (12 inches * 12 inches * 0.44 psi) 62 pounds (if the box is 1 meter square and submerged 1 meter deep, the upward force is 9,800 newtons). This just happens to exactly equal the weight of the cubic foot or cubic meter of water that is displaced!

It is this upward water pressure pushing on the bottom of the boat that is causing the boat to float. Each square inch (or square centimeter) of the boat that is underwater has water pressure pushing it upward, and this combined pressure floats the boat. "

Answer 5

The weight and the dimension of the object

Here is the question my 4th grade teacher asked our class: a ball made out of bronze, you throw it into the water, it sinks. But take the same ball and make it into a flat, thin plate; put it in the water and it will float. WHY?

Different dimensions. The weight is not the only element.

Look at the Titanic, it's humongous. You bet it's heavy but it floats.

Answer 6

Size and the shape and weight of an object even iron floats in the right shape.

Answer 7

If the weight of the water displaced is greater than the weight of the object, it will float.

Answer 8

If the weight of the object is lighter than the weight of the same volume of water, it will float. I think.... :~#

Answer 9

you will possibly desire to remember, that density isn't the only reason products drift. The ships have info that have plenty extra good density, and that they drift through place they have in water. yet fill them with water and that they are going to sink. The regulations of physics "artwork" right here besides!

Answer 10

if the object is solid than its goin down. if the object is empty on the inside it will float

e.g. a ship will float ( cuz its empty on the inside)
a rock will go down cuz its solid