Buoyancy is measured by determining the buoyant force acting on an object immersed in a fluid. This force can be calculated in two primary ways, both rooted in Archimedes' principle.
Methods for Measuring Buoyancy:
There are two main approaches to measuring buoyancy:
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Direct Measurement of Displaced Fluid:
- Measure the mass of the fluid displaced by the object. The weight of this displaced fluid is equal to the buoyant force.
- Alternatively, measure the volume of the displaced fluid and multiply it by the fluid's density to determine the mass of the displaced fluid. Again, the weight of this displaced fluid is equal to the buoyant force.
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Calculating Buoyant Force:
- After determining the mass of the displaced fluid (either directly or through volume and density), multiply this mass by the acceleration due to gravity (approximately 9.8 m/s²) to calculate the buoyant force.
Formula:
Buoyant Force (Fb) = mass of displaced fluid × acceleration due to gravity
Fb = mdisplaced fluid × g
Example:
Suppose an object displaces 0.5 kg of water. The buoyant force acting on the object is:
Fb = 0.5 kg × 9.8 m/s² = 4.9 N
Therefore, the buoyant force is 4.9 Newtons.
Summary:
Buoyancy is measured by quantifying the buoyant force, which is equivalent to the weight of the fluid displaced by an object. This can be achieved either by directly measuring the mass of the displaced fluid or by calculating it from the fluid's volume and density, and then applying the acceleration due to gravity.
