10 Density Examples

The density is a magnitude which measures the amount of mass a material has per unit volume.

The density of a substance depends on the temperature and the Pressure. Generally, by increasing the temperature decreases the density of a material. For example, lead has a density of 11.3 g / cm³ at 20 ºC, that of milk is 1.03 g / cm³ at 15 ° C and that of carbon monoxide, a very toxic gas for humans, is just 0.00125 g / cm³ at 0 ° C. Solid bodies tend to have a higher density than liquids and these in turn have a higher density than liquids. gases.

Density can be classified into:

Where (X), m (X) Y V (X) are the density, mass and volume of the substance X respectively.

Where relative is the relative density of the substance of the substance X with respect to the density of the substance Y, and where (X) Y (Y) are the densities of the substances X and Y respectively.

If a package contains Styrofoam ballsFor example, and a second package, of similar size, contains ceramic tiles, it is clear that the second is going to weigh much more than the first. Density is a characteristic property that makes it possible to identify the different

substances.

The foam mattresses, which are made with a material called polyurethane or polyester, can have different densities and this determines, in part, their quality and durability. In this case, the density of the foam is expressed in kilograms per cubic meter (kg / m³).

The minimum recommended density for making mattresses is 22 kg / m³. Dense mattresses become heavier but are considered better to avoid low back pain problems and spinal deformation; they are also more durable.

The materials porous and less dense they are usually useful as insulators temperature and sound. These materials typically float on water, like cork or plastic.

The figurative sense of "dense"

By extension of this concept of physical density it is said, figuratively (that is, not literally) that something is dense when it demands a lot of attention or concentration to be understood, either because of how difficult or troublesome it is.

For example, a topic is classified as “dense” when it is conflictive; a book or movie can be called "dense" or "dense" in this sense as well. Even a subject of study that requires a lot of effort in abstraction or memorization can be classified by students as "dense."

Population density

On the other hand, population density is a demographic concept that accounts for the number of individuals per unit area (human, animal or plant).

Examples of density

Examples of different densities of chemical elements or complex materials, and population density of cities:

1. Naphtha density: 0.70 g / cm³
2. Density of ice (at 0 ºC): 0.92 g / cm³
3. Mercury density (at 20 ºC): 13.6 g / cm³
4. Density of a standard foam mattress: 28 kg / m³
5. Population density of Mexico City (year 2010): 5862 inhabitants / km²
6. Paraná pine wood density (dry): 500 kg / m³
7. Black locust wood density (dry): 800 kg / m³
8. Density of helium (gas with which flying balloons are inflated) (at 20 ºC): 0.000178 g / cm³
9. Uranium density (at 20 ° C): 19.1 g / cm³
10. Density of regenerating trees in the Andean-Patagonian forest: 20,000 to 40,000 specimens / ha.