Question

A block of wood floats in water with 4/5th of its volume submerged, but it just floats in a liquid. What is the density of the liquid ?

Answer 1

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Answer 2

According to Archimedes' principle: when ⅘th of the block wood is submerged under water of its volume, the density of wood is 4/5 of water’s density -

p(wood) = 4/5p (water) = 800 kg/m3

Now, if the wood is floating in any other liquid, the density of the floating wood is similar to the density of the liquid.

p(wood) = p (liquid) = 800 kg/m3

Hence, the density of the liquid is 800 kg/m3.