Specific gravity and density are measures of the:

Correct option is D

Specific gravity and density are quantitative physical properties that relate directly to the weight of the fiber in relation to its volume. Density is the mass of a fiber per unit volume, commonly expressed in grams per cubic centimeter (g/cm³). Specific gravity is a dimensionless number representing the ratio of the density of the fiber to the density of water. These measures help determine how heavy or light a fiber is, which influences fabric weight, feel, and performance.
Information Booster: In textiles, knowing the density and specific gravity of fibers aids in choosing appropriate materials for different end-uses. For example, lightweight fibers like polyester (with low density) are preferred for summer clothes due to breathability and comfort. Conversely, heavier fibers such as wool provide warmth and durability, beneficial for cold climates. Specific gravity also influences fabric processing behaviors such as dye uptake and blending compatibility. Accurate measurement of these properties is critical in textile manufacturing to ensure the desired fabric weight and hand feel.
Additional Knowledge:
· (a) Colour shade of the fiber: Colour shade refers to the visual tone and intensity of fiber color, typically measured by spectrophotometers or colorimeters, not density.
· (b) Flexibility of the fiber: Flexibility indicates how easily a fiber can bend without breaking, assessed through mechanical testing methods such as bending or torsion tests.
· (c) Appearance of the fiber: Includes characteristics like luster, texture, and uniformity but does not quantify fiber weight or density.