Calculate Density of Wood & Oil: Fluids & Density Homework

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To calculate the density of the wood and oil, the problem involves a block of wood floating in water and oil with specific volumes submerged. Using the principle of buoyancy, the density of the wood can be determined by the ratio of the submerged volume to the total volume in water. The density of the oil can similarly be calculated based on how much of the wood is submerged in it. The hint provided suggests that if the wood's density equals that of water, it would be partially submerged, aiding in the calculations. Overall, the discussion emphasizes understanding buoyancy principles to solve the homework problem effectively.
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Homework Statement



A block of wood with volume V floats in water with 0.67V submerged. In oil the block floats with 0.88V of its volume submerged.
(a) Find the density of the wood.


g/cm3

(b) Find the density of the oil.


g/cm3

I honestly have no idea where to begin. I started off with FB = pVg. rearranged it to p = FB/Vg. Plugged in p = Fb/(0.67V)(9.81). That's all the further I got. We won't even get to this in lecture but the prof still insists we do this webassign.
 
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Hint: If the density of the block of wood exactly equals to that of water and is careflully placed in the water, what part of the wood would be under water?
 
wow. that was so easy I almost feel embarrassed now. Thanks for the help though
 
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