Category
page 1Dimensionless numbers of physics
quantum number
notation for conserved quantities in physics and chemistry
Poisson's ratio
parameter of elastic materials: ratio of transverse strain to axial strain
transparency
property of an object or substance to transmit light with minimal scattering

Total internal reflection
physical phenomenon
f-number
right|thumb|320px|Diagram of decreasing apertures, that is, increasing f-numbers, in one-stop increments; each aperture has half the light-gathering area of the previous one.
Rockwell scale
Rockwell hardness scale based on indentation hardness of a material with a 120° diamond spheroconical under 150 kgf
Abbe number
material dispersion property
numerical aperture
dimensionless number that characterizes the range of angles over which the system can accept or emit light

reflectance
thumb|Spectral reflectance curves for aluminium (Al), [[silver (Ag), and gold (Au) metal mirrors at normal incidence]]
Van 't Hoff factor
abnormal molecular mass
reflection coefficient
measure of wave reflectivity
Hagen number
dimensionless number used in forced flow calculations

Weinberg angle
electroweak coupling constant describing the position of the electromagnetic U(1) within the electroweak gauge group; the arccosine of the W-boson/Z-boson mass ratio
Shore durometer
hardness testing machine
Rouse number
non-dimensional number in fluid dynamics
Blake number
nondimensional number showing the ratio of inertial force to viscous force