A motif is a recurring symbol which takes on a figurative meaning. We see them in books, films, and poems. In fact, almost every text commonly uses the literary device of the motif. A motif can be almost anything: an idea, an object, a concept, a character archetype, the weather, a color, or even a statement.
The Specific Gravity of liquids and solids is defined as a dimensionless unit which is the ratio of density of a material to the density of water at a given temperature, where density is defined as the materialâs mass per unit volume and is measured in kg/m 3.
From Wikipedia: Specific gravity is the ratio of the density of a substance to the density of a reference substance; equivalently, it is the ratio of the mass of a substance to the mass of a reference substance for the same given volume. As a ratio, it is dimensionless - there is no unit of measure. It does not matter what units you use for the mass of the substance and the reference, as long as they are the same units.