A cubical box of wood of side 30 cm weighing 21.6 kg floats on water with two faces horizontal. The depth of immersion of box is

Mass of wooden box = 21.6 kg

Side of cube = 30 cm = 0.3 m

Volume = 0.3 × 0.3 × 0.3 $=27\times {10}^{-3}{\text{m}}^{\text{3}}$

It is said to be floating on water

Then weight of wooden box = Weight of water displaced

$\text{mg}={\text{V}}_{\text{Box}\text{immersed}}\times \text{g}\times {\rho }_w$

$21.6=\text{Base}\text{area}\times \text{h}\times {10}^3{\text{kg/m}}^{\text{3}}$

$21.6=\text{0}\text{.3}\times \text{0}\text{.3}\times \text{h}\times {10}^3$

$\therefore \text{h}=\frac{21.6}{90}=0.24\text{m}=24\text{cm}$