Determine whether the object is floating or not

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SUMMARY

The discussion centers on determining whether a cylindrical object with nonuniform density will float or sink in a liquid of known density. The object's density is defined by the function ρ = 6αH + 4αh, where h is the distance from one end, and the liquid density is ρliq = 9αH. To solve the problem, integration is necessary to calculate the total weight of the object, which allows for a comparison with the buoyant force exerted by the liquid. The outcome will reveal the object's floating orientation and the submerged volume if it floats, or the normal force if it sinks.

PREREQUISITES
  • Understanding of fluid mechanics principles, particularly buoyancy.
  • Knowledge of integration techniques for calculating mass and weight.
  • Familiarity with nonuniform density functions and their implications in physics.
  • Ability to analyze forces acting on submerged objects.
NEXT STEPS
  • Learn about Archimedes' principle and its application in buoyancy problems.
  • Study integration methods for calculating mass from variable density functions.
  • Explore the concept of stable equilibrium in floating objects.
  • Investigate the relationship between density, volume, and buoyant force in fluid mechanics.
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Students studying fluid mechanics, physics educators, and anyone interested in solving buoyancy-related problems involving nonuniform density objects.

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I have this homework question in fluids.
A cylindrical object has one of its flat ends painted red and the other painted green. It has a radius R and height H and has a nonuniform density given by the function ρ = 6αH + 4αh where h is the distance measured from the red end, and α is a positive number with units of density per length.
(a) Will this object float in a container of liquid of density ρliq = 9αH or will it sink? (Make an argument using math.)
(b) If it floats, what orientation will it float in stable equilibrium, and how much of the cylinder will be submerged? If it sinks what is the normal force that the base of the container exerts on the cylinder? (Either way, draw a diagram.)

Here is my answer so far: i know that to determine if the object is float or sink, we compare the density of the object and density of the liquid.
My concern is that: how can I proceed when the density of object is not constant (nonuniform)?
 
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thumn said:
I have this homework question in fluids.
A cylindrical object has one of its flat ends painted red and the other painted green. It has a radius R and height H and has a nonuniform density given by the function ρ = 6αH + 4αh where h is the distance measured from the red end, and α is a positive number with units of density per length.
(a) Will this object float in a container of liquid of density ρliq = 9αH or will it sink? (Make an argument using math.)
(b) If it floats, what orientation will it float in stable equilibrium, and how much of the cylinder will be submerged? If it sinks what is the normal force that the base of the container exerts on the cylinder? (Either way, draw a diagram.)

Here is my answer so far: i know that to determine if the object is float or sink, we compare the density of the object and density of the liquid.
My concern is that: how can I proceed when the density of object is not constant (nonuniform)?
Use integration to figure out the total weight, and the volume is fixed by the rigid container's dimensions.
 
thumn said:
I have this homework question in fluids.
A cylindrical object has one of its flat ends painted red and the other painted green. It has a radius R and height H and has a nonuniform density given by the function ρ = 6αH + 4αh where h is the distance measured from the red end, and α is a positive number with units of density per length.
(a) Will this object float in a container of liquid of density ρliq = 9αH or will it sink? (Make an argument using math.)
(b) If it floats, what orientation will it float in stable equilibrium, and how much of the cylinder will be submerged? If it sinks what is the normal force that the base of the container exerts on the cylinder? (Either way, draw a diagram.)

Here is my answer so far: i know that to determine if the object is float or sink, we compare the density of the object and density of the liquid.
My concern is that: how can I proceed when the density of object is not constant (nonuniform)?
Sooner or later, you'll need to find the mass of the object. This will make it easier to determine if it is floating than by comparing the density of the object (which is non-uniform) with the density of the fluid.
 
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