密度

Also known as volumetric mass density, volumic mass, density

Density (volumetric mass density or specific mass) is the ratio of a substance's mass to its volume. The symbol most often used for density is ρ (the lower case Greek letter rho), although the Latin letter D (or d) can also be used: \rho = \frac{m}{V}, where ρ is the density, m is the mass, and V is the volume. In some cases (for instance, in the United States oil and gas industry), density is loosely defined as its weight per unit volume, although this is scientifically inaccurate this quantity is more specifically called specific weight.

AI overview

Mass density measures how much mass is packed into a given volume of a substance, calculated by dividing the mass by the volume. It's useful for understanding and comparing materials—for example, why lead feels heavier than wood of the same size, or for practical applications like determining whether something will float or sink in water.

AI-generated from the Wikipedia summary — may contain errors.

Key facts

Physical quantity.name: Density
Physical quantity.image: Density column.JPG
Physical quantity.image_size: 100px
Physical quantity.caption: A test tube holding four non-miscible colored liquids with different densities
Physical quantity.unit: kg/m3
Physical quantity.symbols: ρ, D, d
Physical quantity.dimension: wikidata
Physical quantity.extensive: No
Physical quantity.intensive: Yes
Physical quantity.conserved: No
Physical quantity.derivations: \rho = \frac{m}{V}
Physical quantity.otherunits: g/cm3

via Wikipedia infobox

Wikidata facts

Show 8 more facts

Commons category: Density
topic's main category: Category:Density
different from: surface density
opposite of: specific volume
quantity symbol (string): ρ
on focus list of Wikimedia project: Wikipedia:Vital articles/Level/4
maintained by WikiProject: WikiProject Mathematics
Stack Exchange tag: physics.stackexchange.com/tags/density

Sources (4)

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Article · 日本語

密度（みつど）は、一般には、対象とする何かの混み合いの程度を示す語である。ただし、科学において、単に密度といえば、単位体積あたりの質量(質量の空間微分)を指すことが多い。広義には、ある量（物理量など）が、空間（3次元）あるいは面上（2次元）・線上（1次元）に分布していたとして、これらの空間・面・線の微小部分上に存在する当該量と、それぞれ対応する体積・面積・長さに対する比のことを言う（それぞれ、体積密度・面密度・線密度と呼ぶ）。微小部分は通常、単位体・単位面積・単位長さ当たりに相当する場合が多い。勿論、4次元以上の仮想的な場合でもこの関係は成立し、密度を定義することができる。その他の密度としては、状態密度・電荷密度・磁束密度・電流密度・数密度など様々な量（物理量）に対応する密度が存在する（あるいは定義できる）。物理量以外でも人口密度・個体群密度・確率密度、などの値が様々なところで用いられている。密度効果という語もある。

Abstract from DBpedia / Wikipedia · CC BY-SA