Calculate Density of Wood & Oil: Fluids & Density Homework

[scarne92]

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 F_B = pVg. rearranged it to p = F_B/Vg. Plugged in p = F_b/(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.

 

[LawrenceC]

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?

 

[scarne92]

wow. that was so easy I almost feel embarrassed now. Thanks for the help though