Welcome to our buoyancy calculator! The buoyancy force is the upward force that a fluid exerts on a submerged object, countering the object's weight.
Here, you will find an overview of the concept of buoyancy and will be able to calculate upthrust (the buoyancy force on an object in a fluid).
Calculation
Inputs
Density of Fluid, kgm^-3
:997
Volume of Displaced Fluid
:0.25m3
Advanced:
Acceleration Due to Gravity , ms^-2
:9.81
Output
Buoyancy Force
:2,445N
Explanation
As we know from calculating the static pressure in a fluid, pressure increases with depth. If we consider a column of fluid, the pressure at the bottom is greater than the pressure at the top.
In this same way, the pressure at the bottom of a submerged object is greater than the pressure at the top of the object. This results in a net upward force due to the pressure difference and is proportional to this difference in pressure. As explained by Archimedes' principle, this force is equal to the weight of the fluid displaced by the object.
Buoyancy force on a submerged object
⛵️ Archimedes Principle
Presented in 'On floating bodies' (c. 246 BC), Archimedes' principle is a fascinating concept that can be summed up like this: any object partially or fully immersed in a fluid is buoyed up by a force equal to the weight of the fluid displaced by the object.
This means that the downward force on the object is equal to its weight, while the upward (or buoyant) force is determined by the weight of the fluid displaced by the object. The net force on the object is then the difference between the buoyant force and the object's weight. If the net force is positive, the object will rise; if it is negative, the object will sink; and if it is zero, the object will remain in place and remain neutrally buoyant.
In other words, the upward force on the object is what allows the buoyancy of any floating object to be calculated. Therefore, the net force on the object is the difference between the magnitudes of the buoyant force and its weight.
We calculate buoyancy force using the following equation: