How to Relate Densities, Height, and Time for a Sinking Solid?

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vampulski
It has been a long time since I have worked with this and I need help just starting out.

The problem involves the density of a liquid, the density of a solid, and the height where the solid will be released in the liquid, gravitational force, and the time it takes to reach the top of the liquid.

I don't want answers, I just need help starting with this. Is there any equation that relates height to these 2 densities and time? Does it involve taking the difference between 2 forces, liquid and solid?

Thank you in advance.
 
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vampulski said:
It has been a long time since I have worked with this and I need help just starting out.

The problem involves the density of a liquid, the density of a solid, and the height where the solid will be released in the liquid, gravitational force, and the time it takes to reach the top of the liquid.

I don't want answers, I just need help starting with this. Is there any equation that relates height to these 2 densities and time? Does it involve taking the difference between 2 forces, liquid and solid?

Thank you in advance.
Welcome to the PF. :smile:

Can you post a sketch of the situation? Your description so far doesn't seem to completely describe the problem...

You can Upload the image of your sketch (PDF or JPG) bu using the UPLOAD button in the lower right.
 
Khashishi said:
It sounds like you are talking about buoyancy. Wikipedia has a decent article. https://en.wikipedia.org/wiki/Buoyancy

The time it takes for an object to move through liquid will also depend on the viscosity of the liquid and shape of the object.
It does not involve viscosity or shape of object, it just asks to do dimensional analysis to find equations that relate time to h(distance from object to surface), density of liquid, density of object, and g(gravity). I just need a start, maybe some equation(s) that can help relate these variables.
 
vampulski said:
I just need a start, maybe some equation(s) that can help relate these variables.

well as you were asked, please explain this more clearly, it doesn't make much sense ...

vampulski said:
The problem involves the density of a liquid, the density of a solid, and the height where the solid will be released in the liquid, gravitational force, and the time it takes to reach the top of the liquid.

people may be able to help you if you help them with a clearer description with drawingsDave
 
vampulski said:
It has been a long time since I have worked with this
vampulski said:
It does not involve viscosity or shape of object, it just asks to do dimensional analysis to find equations that relate time to h(distance from object to surface), density of liquid, density of object, and g(gravity).
This is starting to sound like schoolwork. Perhaps you should re-post in the Homework Help, Introductory Physics forum, and fill out the Template that you are provided there. Be sure to fill out the sections on the Relevant Equations, and show your Attempt at a Solution.

This obtuse thread in the general technical forums is now closed. Thanks everybody for trying to help.