核心畫面

Picture a fixed box and ask how much has been into it. Not how big, not how many — how much per box. That ratio is the word, and it works the same whether the box holds people on a map or matter in a lump of metal.

可以想成:拿一個固定大小的箱子,問裡面塞了多少東西。不是問有多大,也不是問有幾個,而是問「每一個箱子裡有多少」。這個更多收起可以想成:拿一個固定大小的箱子,問裡面塞了多少東西。不是問有多大,也不是問有幾個,而是問「每一個箱子裡有多少」。這個比值就是這個字;不管箱子裡裝的是地圖上的人口,還是一塊金屬裡的物質,算法是同一套。

From the picture

物理上的密度

同一個比值換成科學上的量:分母從面積變成體積,分子從人數變成質量。

mass per volume · noun · C1

In science, how heavy something is for its size — its mass compared to the space it takes up.

密度

Also in this word

how closely packed · noun · C1

How much of an area is filled with people or things — how closely packed they are.

密度

原始詞典資料4 筆記錄

以下是外部詞典記錄的用法,原文照列,我們還沒有寫成教學內容。上面的說明才是我們自己寫的;有些用法可能上面已經講過了。

densitynoun/ˈdɛn.sɪ.ti/

  • 1

    natural-sciencesphysical-sciencesphysicsThe amount of a certain phenomenon (such as stuff, things, energy, or otherwise) in a given area (surface area) or volume (amount of space).

    • In the past two years, NASA’s Kepler Space Telescope has located nearly 3,000 exoplanet candidates ranging from sub-Earth-sized minions to gas giants that dwarf our own Jupiter. Their densities range from that of styrofoam to iron.
    • The microcannon was seen moving at about a micron per second, it was about 15 microns long, and the high speed photograph was done in water (density of 1 kg/L, viscosity of about 0.001 pascal seconds).
  • 2

    The amount of a certain phenomenon (such as stuff, things, energy, or otherwise) in a given area (surface area) or volume (amount of space).

    • The number of particles per unit volume of a specified volume can be considered to be the particle density for the specified volume.
    • Density, which is genetically linked, deals with the number of strands per square inch on your scalp. Normal density can range from slight to substantial, varying from person to person.
  • 3

    mathematicssciencesstatisticsThe probability that an outcome will fall into a given range, per unit of that range; the relative likelihood of possible values of a continuous random variable.

  • 4

    Stupidity.

    • There's only so much density that pedagogy can penetrate.

資料來源:英文維基詞典 English WiktionaryCC BY-SA 4.0)。 原文照列,未經改寫。