Container of Liquid Accelerated Upward

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SUMMARY

The discussion centers on the behavior of a block floating in a liquid when the entire container is accelerated upward. The initial reasoning concluded that the block would descend lower into the liquid due to an increase in buoyant force, but the correct conclusion is that the block does not ascend or descend. This is explained through Archimedes's principle, which states that the buoyant force equals the weight of the displaced liquid, and the perceived increase in gravity during acceleration does not affect the block's floating condition.

PREREQUISITES
  • Understanding of Archimedes's principle
  • Familiarity with Newton's laws of motion
  • Knowledge of buoyancy and fluid mechanics
  • Basic concepts of acceleration and forces
NEXT STEPS
  • Study the implications of Archimedes's principle in different gravitational fields
  • Explore the effects of acceleration on fluid dynamics
  • Learn about buoyancy in non-inertial reference frames
  • Investigate the relationship between buoyant force and displaced volume
USEFUL FOR

Physics students, educators, and anyone interested in fluid mechanics and the principles of buoyancy in accelerated systems.

Chozen Juan
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Homework Statement



A block floats partially submerged in a container of liquid. When the entire container is accelerated upward, which of the following happens? Assume that both the liquid and the block are incompressible.

A) The block descends down lower into the liquid.
B) The block does not ascend or descend in the liquid.

Homework Equations



ρ = M/(Volume)
W = Mg
F = ma
Archimedes's principle

The Attempt at a Solution



I figured that when the block floats partially submerged and is not accelerating, the buoyant force on the block is equal to the block's weight.

When the block is accelerated upward, then there must be a net upward force on the block; since there are only two forces acting on the block, buoyant force and weight, the buoyant force on the block must increase. Since the buoyant force increases, more of the block's volume must be submerged in the liquid since, by Archimedes's principle, the buoyant force is equal to the weight of the displaced liquid. More liquid should be displaced now, so the block must descend. I chose answer A.

The correct answer, however, is B.
What is wrong with my reasoning?
 
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When a system accelerates it's just as if you have increased gravity ...Remember astronauts in a rocket taking off from Earth ..they experience 5 or 6 g because the rocket is accelerating at 4or 5 g ...inside the rocket it feels the same as it would if the Earth's gravity had just magically increased.

So the question is... is the way the block floats dependent on the gravity it experiences , On the moon would it float the same as on Earth ?
 
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