Finding Mass of an Object [Fluid Mechanics]

AI Thread Summary
A wooden cube with a 20.0 cm edge and a density of 650 kg/m^3 floats on water, with 7.0 cm of its height above the water level. To determine how much lead is needed to make the cube's top level with the water, the volume of the cube is calculated to be 8000 cm^3. The user struggles with finding the mass of lead required, indicating a need to apply the formula V = m/d. The correct mass of lead to achieve this balance is 2.80 kg. Understanding the relationship between volume, mass, and density is essential for solving this fluid mechanics problem.
Minihoudini
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A cube of wood having an edge dimension of 20.0 cm and a density of 650kg/m^3 floats on water. a) what is the distance from the horizontal top surface of the cube to the water level?
b)what mass of lead should be placed ont eh cube so that the top of the cube will be just level with the water?

A is 7.0cm
B is 2.80kg


Vfluid/Vobject= Dobject/Dfluid

I figured out how do to the first part but I am having trouble trying to find out part B.
I know you have to use V=m/d but the problem is I can't seem to find volume.
 
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What's the volume of a cube?
 
sorry its 8000cm^3
 

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