Fluid mechanics,wooden block in water and oil

AI Thread Summary
The discussion revolves around a physics homework problem involving a wooden block submerged in water and oil. Key points include calculating the absolute pressure at both the upper and lower faces of the block, and determining the mass and density of the block. The block is in equilibrium with its lower surface 2 cm below the interface between the two liquids, and the density of the oil is given as 790 kg/m3. The user expresses confusion about the pressure calculations and the dimensions of the block, indicating urgency due to an upcoming exam. Assistance is sought to clarify these concepts and solve the problem effectively.
hannam
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Homework Statement


A cubical block of wood, 10 cm on a side, is placed in a
glass cup whose higher end is open to the atmosphere. The
wood is in equilibrium at the interface between water and oil
with wood’s lower surface 2 cm below the interface. The
density of oil is 790 kg/m3.
a) What is the (absolute) pressure at the lower and upper face of
the wood block?
b) What are the mass and density of the block?

Homework Equations



fb=p liquid * v sinked*g
p object * v object = p liquid * v sinked
P1= Po+ p*h*g

The Attempt at a Solution


0.02*1 + 790*x = p wood*(2+x) =m
does it say edge of the wood is 10 cm? my english is not very good and if it is 10 cm, i can find m.
but still i have no idea about the pressure part.
my exam is tomorrow. any help is appreciated :(
 
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