Upthrust in water with different gravity

AI Thread Summary
When a cork floats half submerged in water on Earth and is then moved to an area with lower gravity, the submerged proportion of the cork will remain the same. This is because the buoyancy force, which is equal to the weight of the fluid displaced, is affected equally by the change in gravity for both the cork and the water. The volume of the cork does not change, so the relationship between the cork's weight and the buoyant force stays consistent. Therefore, the cork will maintain its position relative to the water's surface. The discussion emphasizes that the principles of buoyancy remain unchanged despite variations in gravitational acceleration.
Scarlet_pat
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Homework Statement




A small cork floats in water, exactly half submerged, on Earth. If the container,
water and cork were all transferred to a place where the acceleration due to
gravity is less than that on Earth, would the submerged proportion of the cork
be greater. stay the same or become less?


give 2 reasons for your answers

The Attempt at a Solution



The submerged proportion of the cork will become less.

Because the volume remains constant while the weight of the object changed due the different gravity.
the upthrust force will be greater than the force of the object exerted.

Question: is the answer correct? it is quite plausible because the weight of the water has also changed. Does it affect the upthrust force? or volume and destiny are the only elements which will affect the upthrust force of liquid.

thank you very much :)
 
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If the value of g changes, then it affects the weights of all things equally. That includes the weight of the water displaced by a given volume, which determines the magnitude of the buoyancy force.
 


the net upward buoyancy force is equal to the magnitude of the weight of fluid displaced by the body. and therefore... the floating object will remains at it's original position ... right ?
thanks for reply :)
 


Scarlet_pat said:
the net upward buoyancy force is equal to the magnitude of the weight of fluid displaced by the body. and therefore... the floating object will remains at it's original position ... right ?
thanks for reply :)

The magnitude of the buoyancy force is equal to the weight of the fluid displaced by the body, right.

The weights of the body and the water are both determined by the local g, which behaves as a simple proportionality constant for the underlying masses. The ratios and relationships that determine buoyancy effects remain the same.
 


gneill said:
The magnitude of the buoyancy force is equal to the weight of the fluid displaced by the body, right.

The weights of the body and the water are both determined by the local g, which behaves as a simple proportionality constant for the underlying masses. The ratios and relationships that determine buoyancy effects remain the same.

thanks for such sophisticated explanation :)
 
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