You must discover it's mass (weight) AND it's volume.
(Then divide to get pounds per cubic foot)
-- Measure its mass. -- Measure its volume. -- Divide the mass by the volume. The result of the division is the object's density.
It's all about density; figure out the density of the liquid and the density of the object. If the object is less dense than the liquid, it will float. It's a matter of buoyancy and Archimedes' principle.
You don't know the density if you only know the mass. You can figure it out if you also know the object's volume.
Density is calculated by dividing the mass of an object by its volume. The formula for density is D = m/V, where D is density, m is mass, and V is volume. The unit of density is typically grams per cubic centimeter (g/cm^3).
The density of a liquid affects the buoyancy of an object by determining whether the object will float or sink in that liquid. If the density of an object is greater than the density of the liquid, the object will sink. If the density of the object is less than the density of the liquid, the object will float.
An object will float in a fluid if its density is less than the fluid's density. If the object's density is greater than the fluid's density, the object will sink. If the object's density is equal to the fluid's density, it will be suspended at a specific depth.
Since the DENSITY of WATER = 1, and the Weight is 14 Newtons (in air) and 3 Newtons (Submerged in Water) we can figure the Density of the Object by the following: N = kg·m/s2 14 N = (Mass of Object) x 9.81 m/s2 (Mass of Object) = 14 N / 9.81 m/s2 (Mass of Object) = 1.427 kg And Since IN WATER the Object is 3 Newtons: 3 N = (1.427 kg x 9.81m/s2 ) / (Density of Object) 3 N = (14 N) / (Density of Object) Density of Object = (14 N) / (3 N) Density of Object = 4.6667
To predict the density of a floating object, you can compare the density of the object to the density of the fluid it is floating in. For an object to float, its density must be less than the density of the fluid. You can calculate the density of the object by dividing its mass by its volume.
the specific gravity is how the density of the object compares to the density of water. Water's density is 1gram per milliliter. We just need to figure out the density of the object. The object is .8 kg and it displaces 500mL of water, so the density is the mass divided by the volume. Since the density of water is given in grams, we have to convert the objects mass from kg to g and then we can get the density. .8kg * 1000g/kg = 800 grams so, 800g/500ml = 1.6grams/mL this is the density. So divide the density of your object by the density of water, which is 1g/mL, you get 1.6 as the specific gravity. This means the object is 1.6 times more dense than water.
the specific gravity is how the density of the object compares to the density of water. Water's density is 1gram per milliliter. We just need to figure out the density of the object. The object is .8 kg and it displaces 500mL of water, so the density is the mass divided by the volume. Since the density of water is given in grams, we have to convert the objects mass from kg to g and then we can get the density. .8kg * 1000g/kg = 800 grams so, 800g/500ml = 1.6grams/mL this is the density. So divide the density of your object by the density of water, which is 1g/mL, you get 1.6 as the specific gravity. This means the object is 1.6 times more dense than water.
If an object has less density than water (or whatever liquid you are considering), it will float. And if it has more density then the liguid you are considering it will sinq
density of the object < density of the fluid