Question

The ratio of the speed of light in a vacuum to the speed of light in a particular material is called what?

• A. the coefficient of diffraction of the material.
• B. the index of refraction of the material
• C. the coefficient of refraction to the material
• D. the index of diffraction of the material.
• E. the modulus of diffraction of the material.

Answer 1

The correct option is B the index of refraction of the material

The refractive index of a material is defined as the ratio of speed of light in vacuum to the speed of light in a particular material.

$\therefore$ Refractive index of a material $n=\frac{V_{vacuum}}{v_{material}}$