B How Does Liquid Density and Viscosity Influence Free Fall Braking?

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Liquid density and viscosity significantly influence the behavior of objects in free fall through fluids. The buoyancy experienced by an object is determined by its density relative to the liquid, affecting how quickly it descends. In a liquid like glucose, which has a lower density than gold and stone, the denser objects will experience greater buoyant forces, potentially slowing their fall. Viscosity also plays a crucial role, as it contributes to the drag force acting on the falling objects, impacting their terminal velocity. Understanding these factors is essential for predicting the motion of different density objects in liquids.
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If two objects with big diffrence in density but the same size travel through a liquid closer to the density of one of the objects, does it slow down the free fall?
In mine hypothesis I want to slow down free fall for diffrent density objects in liqudies. I have a stone wich i roughly a denisty of 2,7 g/ml and gold with 19,7 g/ml. They have the same size. Liquied glucose has the density of roughly 1,5 g/ml. In my example, I drop at the same time in a 1 meter pipe with glucose. How does the density affect the buoyancy with free fall? Does Viscosity matter in this case? Will gold fall faster?
Thank you for your help with trying to sort this out.
 
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Welcome to PF. :smile:

It certainly seems like it will have some effect. Can you post links to the reading you have been doing so far on this question?

Also, is this question for schoolwork? Thanks.
 
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Arbegator said:
How does the density affect the buoyancy with free fall? Does Viscosity matter in this case?
Density is important because the driving force is due to the weight, less the buoyancy of the object in the fluid.

Viscosity is critical in that it is part of the drag equation. Terminal velocity is reached when the falling body drag balances the driving force.
https://en.wikipedia.org/wiki/Drag_(physics)#Very_low_Reynolds_numbers:_Stokes'_drag
 
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