## Refractive index of mercury

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A dimensionless quantity is a quantity with no physical dimension, also known as a bare, pure, or scalar quantity or a quantity of dimension one,[1] with a corresponding unit of measurement in the SI of the unit one (or 1),[2][3] which is not clearly seen in dimensional analysis. Many areas, including mathematics, physics, chemistry, engineering, and economics, use dimensionalless quantities. Quantities of corresponding dimensions, such as time, are distinct from dimensionalless quantities (measured in seconds).
Dimensionless quantities, or those with only one dimension, are common in science and are formally studied in the field of dimensional analysis. French mathematician Joseph Fourier and Scottish physicist James Clerk Maxwell led important advances in modern conceptions of dimension and unit in the nineteenth century. Osborne Reynolds and Lord Rayleigh, two British physicists, later contributed to the interpretation of dimensionless numbers in physics. Edgar Buckingham proved the theorem (independently of French mathematician Joseph Bertrand’s previous work) to formalize the existence of these quantities, based on Rayleigh’s method of dimensional analysis. [number four]

## Refractive index of glass

We’ll look at refractive indices, refraction, total internal reflection, and the refractive index of plastics in this article. We’ll also look at why polymer optics instead of glass could be a better choice for your project.
As light enters a material, the refractive index determines how much the direction of light is refracted or bent. Snell’s law of refraction describes this effect. The refractive indices also specify the amount of light reflected at the interface, as well as the critical angle for total internal reflection (more on that later), their intensity (Fresnel’s equations), and Brewster’s angle (more on that later).
The refractive index varies depending on the wavelength. When white light is refracted, this is what allows it to break into colors (an effect known as dispersion). This effect can be seen in prisms and rainbows, as well as in lenses as chromatic aberration. Across the visible spectrum, the refractive index of most materials varies by a few percent with wavelength. Refractive indices are often recorded with a single n value, which is calculated at 633 nm.

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Different plastics have different refractive indexes. Also, at different wavelengths of light, each plastic has slightly different indexes, though the difference is normally minor. Acrylic, for example, has an index of around #n = 1.498#, while Polystyrene (another plastic) has an index of around #n = 1.604#. These characteristics apply to light with a wavelength of #486.1#nm, which corresponds to the color blue. # n # just equals #1.489# for acrylic with red light (wavelength #= 656.3#nm).
As a result, the index of a block of plastic varies depending on its form, wavelength, and even temperature. However, the most common value is #n=1.5#. Of course, the best method is to test the plastic block.

### Refractive index of plastic and glass

Different plastics have different refractive indexes. Also, at different wavelengths of light, each plastic has slightly different indexes, though the difference is normally minor. Acrylic, for example, has an index of around #n = 1.498#, while Polystyrene (another plastic) has an index of around #n = 1.604#. These characteristics apply to light with a wavelength of #486.1#nm, which corresponds to the color blue. # n # just equals #1.489# for acrylic with red light (wavelength #= 656.3#nm).
As a result, the index of a block of plastic varies depending on its form, wavelength, and even temperature. However, the most common value is #n=1.5#. Of course, the best method is to test the plastic block.