Who invented buoyant force

Create a personalised content profile. Measure ad performance. Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights. Measure content performance. Develop and improve products. List of Partners vendors. Share Flipboard Email. Alane Lim. Science Expert. Alane Lim holds a Ph.

She has published numerous peer-reviewed journal articles on nanotechnology and materials science. Updated September 28, Key Takeaways: Buoyant Force The term buoyant force refers to the upward-directed force that a fluid exerts on an object that is partially or completely immersed in the fluid.

Featured Video. Cite this Article Format. Lim, Alane. Pressure is simply the exertion of force over a two-dimensional area. Thus it is as though the fluid is composed of a huge number of two-dimensional "sheets" of fluid, each on top of the other, like pages in a newspaper. The deeper into the larger body of fluid one goes, the greater the pressure; yet it is precisely this increased force at the bottom of the fluid that tends to push the "bag" upward, against the force of gravity.

Now consider the weight of this "bag. For an object suspended in fluid, it is useful to substitute another term for mass. Mass is equal to volume, or the amount of three-dimensional space occupied by an object, multiplied by density. Since density is equal to mass divided by volume, this means that volume multiplied by density is the same as mass.

We have established that the weight of the fluid "bag" is Vdg, where V is volume, d is density, and g is the acceleration due to gravity. Now imagine that the "bag" has been replaced by a solid object of exactly the same size. The solid object will experience exactly the same degree of pressure as the imaginary "bag" did—and hence, it will also experience the same buoyant force pushing it up from the bottom.

This means that buoyant force is equal to the weight— Vdg —of displaced fluid. Buoyancy is always a double-edged proposition. If the buoyant force on an object is greater than the weight of that object—in other words, if the object weighs less than the amount of water it has displaced—it will float.

But if the buoyant force is less than the object's weight, the object will sink. Buoyant force is not the same as net force: if the object weighs more than the water it displaces, the force of its weight cancels out and in fact "overrules" that of the buoyant force. At the heart of the issue is density. Often, the density of an object in relation to water is referred to as its specific gravity: most metals, which are heavier than water, are said to have a high specific gravity. Conversely, petroleum-based products typically float on the surface of water, because their specific gravity is low.

Note the close relationship between density and weight where buoyancy is concerned: in fact, the most buoyant objects are those with a relatively high volume and a relatively low density. This can be shown mathematically by means of the formula noted earlier, whereby density is equal to mass divided by volume. The Archimedes principle is a very useful and versatile tool.

It can be useful in measuring the volume of irregular objects, such as gold crowns, as well as explaining the behaviors of any object placed in any fluid.

Archimedes' principle describes how ships float, submarines dive, hot air balloons fly, and many others examples, according to Science Clarified. The Archimedes principle is also used in a large variety of scientific research subjects including medical, engineering, entomology, engineering, and geology.

The Archimedes principle has many uses in the medical and dentistry field and is used to determine the densities of bones and teeth. The volume fraction of the cancellous bone can be used in various age and health studies including being an index in aging studies, osteoporosis, bone strength, stiffness, and elasticity studies. Various methods using Archimedes principle were tested in order to increase reproducibility of the measurements: one where the bone was submerged in distilled water, another where the bone was submerged in a water and surfactant solution, and a third where the bone was placed in a sealed container where the changes in gas pressures were recorded.

An article published in in the journal Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology is similar in nature to the previous article where various methods were used in order to determine the reproducibility, one of which was using Archimedes principle. The Archimedes principle was compared with using cone beam computed tomography CBCT to measure the volume of the teeth.

The tests comparing the Archimedes principle and CBCT measurements showed that the latter would be an accurate tool in planning dental procedures. A simple, reliable, cost-effective design for a submarine described in a paper in the journal Informatics, Electronics, and Vision, is based on the Archimedes principle. Submarines, according to the authors, are designed to travel while completely submerged underwater and rely on the Archimedes principle in order to maintain a constant depth.

The design of this prototype submarine uses calculations involving the mass, density, and volume of both the submarine and the displaced water in order to determine the size needed of the ballast tank, which will determine the amount of water than can fill it and therefore the depth to which the submarine can dive.

While the Archimedes principle is used in submarine design to help them dive and resurface, it also explains the reason why some bugs can walk on water. In a study published in Applied Physics Letters, researchers used a method of measuring shadows created by the water striders in order to measure the curvatures in the water surface. These dips can then be used to derive the water volume that was displaced leading to the force used to keep the water-bugs afloat.

The authors said there is a great deal of interest in understanding the physics behind the water-walking bugs in order to create biomimetic water-walking robots. A paper published in in Soft Matter describes a more in-depth view of the Archimedes principle, which the authors call the Generalized Archimedes Principle. The Archimedes principle as it is typically used can only be used as an approximation in many instances of studying sedimentation profiles, while the generalized principle can account for phenomena such as denser particles floating on top of a light fluid.

The authors' key point lies in the density perturbations that are induced by the particles suspended in the fluid, which is not taken into account in the traditional use of the Archimedes principle, and a new approach to the Archimedes principle is derived.