A piece of wood having weight 5 kg floats in water with 60% of its volume under the liquid. The specific gravity of wood is A. 0.83 B. 0.6 C. 0.4 D. 0.3

The correct answer is A. 0.83.

The specific gravity of a substance is its density relative to the density of water. The density of water is 1 g/cm3. The volume of the wood is 5/0.6 = 8.33 cm3. The mass of the wood is 5 kg. The density of the wood is 5/8.33 = 0.60 g/cm3. The specific gravity of the wood is 0.60/1 = 0.60.

Option B is incorrect because the specific gravity of wood is not 0.6. Option C is incorrect because the specific gravity of wood is not 0.4. Option D is incorrect because the specific gravity of wood is not 0.3.

The specific gravity of a substance is a dimensionless number that is equal to the ratio of the density of the substance to the density of a reference substance. The reference substance