We explain what volume is, how it is measured and some examples. Also, what is density and mass.
What is volume?
Volume is understood as a metric, Euclidean and scalar magnitude, which can be defined as the extension of an object in its three dimensions, that is, taking into account its length, width and height. All physical bodies occupy a space that varies according to their proportions, and the measure of that space is the volume.
To calculate the volume of an object, all you have to do is multiply its length by its width and its height, or in the case of geometric solids, apply certain formulas based on area and height or other similar variables. For example:
- Volume of a parallelepiped. v = l x b x h, where l is length, b is width, and h is height.
- Volume of a cube. v = a3, where to is the side of the cube, or to x to x to.
- Volume of a sphere. v = 4/3 x π x r3, where r is the radius.
- Volume of a cylinder. v = π x r2 x h, where h is the height of the cylinder and π x r2 is the surface of the circular base.
- Volume of a cone. v = (π x r2 x h) / 3, where r is the radius of the base.
- Volume of a pyramid. v = 1/3 x to x h, where to is the area of the base.
On the other hand, depending on thestate of matter aggregation and also his temperature, the volume can take various forms. Thus a body solid has a fixed and determined volume, while fluids (liquids Ygases) do not have a fixed volume: they adapt to the space that contains them. Due to temperature variations, the volume of solids, gases and liquids can change, in general they can expand or contract.
How is volume measured?
The unit established in the International system (SI) to measure the volume is the cubic meter (m3), although forto size the capacity (equivalent to the volume but in the presence of fluids) the liters are used. This distinction is due to historical reasons, but they are equivalent measures: a liter (L) is equivalent to a cubic decimeter (dm3). This means that it can also be spoken of cubic kilometers or cubic millimeters, depending on the need.
In the Anglo-Saxon system of measurements, the volume will be measured using feet, inches or cubic yards, or for liquids the barrel, the gallon and the pint. In a culinary field, it is used as a measure of volume to the cup, the tablespoon or the teaspoon, which are less precise but much more practical.
Beakers or test tubes are used to measure the volume of a fluid in a laboratory.
To measure the volume of a solid, it must be immersed in a test tube withWater (whose volume we know) and introduce the solid, to measure the increase in the joint volume. Then the initial volume will be subtracted from the final volume and the volume of the added solid will be obtained.
Volume examples
To exemplify what the volume, you can turn to the capacity of various containers. For example, a glass, a mug, and a bottle have different capacities that represent the volume of space in their shapes.
Another example is the measurements of different materials that are used in a chemical laboratory to carry out a experiment: the cubic centimeters of a solid, the liters of a gas or other fluids.
Density
Density is a scalar quantity that is defined as the amount of mass of an object divided by the volume it occupies. It is usually represented by the Greek letter rho (ρ) and is expressed mathematically as ρ = m / V. The unit of measurement Density according to the International System is the kilogram over cubic meter (kg / m3).
Mass
The mass is a quantity that expresses the amount of matter present in a body, measured by its inertia (that is, your endurance to acquire a acceleration in front of the action of a force). It is an intrinsic property of matter, which is measured according to the International System (SI) in kilograms (kg) and is expressed by the variable m.
This measurement should not be confused with the amount of substance, which is calculated chemically in moles (mole); nor with himweight, which is a vector quantity that represents the intensity with which theforce of gravity acts on a massive body, measured according to the International System in Newtons (N).