The piece of wood sinks more in kerosine than in water during floating. The density of kerosine is less than that of water. The buoyant force on a body is proportional to the density of the liquid in which the body is immersed. When a body floats, the magnitude of the buoyant force acting on the body is equal to that of the weight of the body.
Hence, the volume of the liquid displaced by a floating body is inversely proportional to the density of the liquid. As a result, when a piece of wood floats in kerosine, it displaces greater volume of kerosine compared to the volume of water displaced when the piece of wood floats in water. Hence, it sinks more in kerosine than in water.
[Note: When a body floats in a liquid fb = fg
∴ Vρ1g = Vbρbg
∴ The volume of the liquid displaced by the body is V = Vb \(\cfrac{\rho_w}{\rho_1}\), where Vb is the volume of the body, ρb is the density of the material of the body and ρ1 is the density of the liquid. Thus, V ∝ 1 /ρ1]
