The V-number, represented by V, is a dimensionless parameter used in optical fiber and waveguide technology. It is calculated as the ratio between the core radius of an o
“DN” is an abbreviated form of Diameter Nominal (DN). It is a dimensionless number that denotes the pipe size in the metric unit system. The DN pipe size designator is developed by the International Standards Organization or ISO and is widely found in Europe and other metric-based countries...
In photography, an F-stop is the ratio of the focal length of the lens to the diameter of the aperture. The number is expressed as a fraction. F-stop is a dimensionless number and gives an important measure of the lens speed. Advertisements An F-stop is also known as a focal ratio o...
A Decibel is a dimensionless number that represents a logarithmic ratio between a quantity and known reference. Sound Decibels are the units with which Sound Pressure Level (SPL) is measured and for which the reference value is {eq}20 \mu Pa. {/eq} Notation for a sound decibel commonly app...
Molar ratio units are either mole:mole or else it is a dimensionless number because the units cancel out. For example, it's fine to say a ratio of 3 moles of O2to 1 mole of H2is 3:1 or 3 mol O2: 1 mol H2. Molar Ratio Example: Balanced Equation ...
Refractive index is a dimensionless number that is used as an indication of the bending ability of light in an optical medium. It is also known asrefraction index. This parameter determines the degree at which the light is bent or refracted upon the light entering a material. ...
F-ratio is one of the most well understood and applied concepts in photography (not just AP). It is a dimensionless number that has been derived to tell any photographer quickly and easily how fast his lens / telescope is and how long he has to expose to get similar luminance comp...
To understand the Reynolds number and its importance, it is necessary first to understand what it is and how to calculate it.
The accelerated test model is derived from testing the key factors of a product under normal stress levels and one or more accelerated stress levels.
Nominal pipe size (NPS) is a dimensionless mark of pipe size. It represents the standard pipe size when it has a specific size code without the inch symbol. For example, NPs 6 represents a pipe with an outside diameter of 168.3 mm. ...