What does density describe in relation to an object?

Density fundamentally describes the relationship between the mass of an object and its volume. In essence, it provides insight into how much matter is contained in a given space. When discussing density, one typically refers to how much an object weighs in relation to its size, which is expressed mathematically as mass per unit volume (e.g., grams per cubic centimeter or kilograms per cubic meter).

Understanding density is crucial in various fields, including sonography, as it affects how sound waves propagate through different tissues and media. Denser materials, for example, may exhibit different acoustic properties than less dense materials, influencing imaging quality and interpretation.

The other options focus on different properties of materials. The strength under tension relates to tensile strength, which is a measurement of how much force a material can withstand while being stretched. Resistance to deformation pertains to a material's elasticity or hardness. Finally, temperature sensitivity reflects how a material's properties change with temperature, which is not directly related to density. All of these aspects are important in physics and material science but do not describe what density itself represents.