|  | Diet Nutrition | Nutrition

What Is a Density Meter?

Density meters measure the density of substances using non-technical language. Such measurements, however, are not easily calculated. A thorough knowledge on the term "density" and the different methods to measure it are required before you should operate devices that can measure density. An oscillating U-tube density meter is the most common device used to measure liquid and gas densities.

  1. Density

    • The term "density" is scientifically defined as “mass per unit volume.” Substances' densities vary with physical conditions and other factors. Sometimes density is measured in terms of specific gravity or relative density. These are unit-less terms and give a measure of the density of a material with respect to some standard substance’s density. Knowing the density of substances is important to carry out calculations and scientific research.

    Homogeneous Objects

    • Homogeneous objects are composed of the same elementary particles--that is, their physical properties do not change with time, space or other factors. The density of a homogeneous solid object can be easily measured using the principles of hydrostatic weighing. It involves simply measuring the density of water displaced by the body when it is submerged in a water body.

    Need for a Density Meter

    • Conventional methods such as hydrostatic weighing and calculating the mass and volume for density are fine for calculating density for homogeneous objects that cannot be easily compressed or that have a fixed volume. However, for substances such as sand and liquids, this method fails to determine the density. Sand can be made to occupy any volume and therefore its density will vary depending on the amount packed in. A density meters can measure the density of such substances.

    A Typical Density Meter

    • A typical oscillating U-tube density meter consists of a hollow glass tube, which holds the substance to be measured. The tube is configured to oscillate at a particular frequency without any load. When a test substance is put in it, the increase in the tube’s mass causes the oscillation frequency of the U-tube to change. This change in frequency is used to determine the relative density of the substance. By calibrating this device to your required system of measurement, such as specific gravity or relative density, you can get an accurate reading.

    Modern-Day Density Meters

    • Differences among density meters lie in their accuracy and stability of measurement. Some costlier laboratory variants can give you multiple readings for every input and are stable at different temperatures. Some types of meters only work on solid objects, while others work on liquid or gaseous objects. Furthermore, portable density meters also help field workers to calculate density using the same oscillating U-tube technology.

Nutrition - Related Articles