How to Calculate Water Pressure on a Floating Cube?

AI Thread Summary
To calculate the water pressure on the base of a floating cube, first determine the depth of the cube submerged in water, which is 3 cm. Using the formula for hydrostatic pressure, the pressure at this depth can be calculated as P = ρgh, where ρ is the density of fresh water (1000 kg/m³), g is the acceleration due to gravity (9.81 m/s²), and h is the depth (0.03 m). This results in a pressure of approximately 294.3 Pa at the base of the cube. Additionally, the density of the wood can be inferred from the buoyancy principle, leading to the conclusion that the density of the wood is 250 kg/m³. Understanding these calculations is essential for solving similar problems involving buoyancy and pressure.
Molly1235
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"A cube of wood of side 4cm floats in fresh water with 1:4 showing above the surface.
Calculate a) the water pressure on the base of the cube and b) the density of the wood"

All I can work out is that the density of fresh water is 1000kgm^-3 and the area of the base is 1.6 x 10^-5 m.

Please can someone help?? I don't know where to start...
 
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How deep (below surface) is the bottom of the cube?
 
nasu said:
How deep (below surface) is the bottom of the cube?

3cm?
 
Right!

Remember that the hydrostatic water pressure strictly depends on the vertical, that is, it doesn't matter whether you calculate the pressure directly BENEATH the cube, or anywhere else along the horizontal line lying 3 cm below the surface.
 
OK, now calculate the pressure at this depth.
 

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