Question

19. To describe the change in
speed of light in a medium,the
term used is called index of
reflection
O refraction
diffraction
acoustic​

Answer 1

Explanation:

In optics, the refractive index (also known asrefraction index or indexof refraction) of a material is a dimensionless number that describes how fast lighttravels through the material. It is defined as. where c is the speed of light in vacuum and v is the phase velocity of light in the medium

Answer 2

To describe the change in speed of light in a medium, the term used is called index of Refraction.

Explanation for the answer:

• The phenomena of the ending of a wave when it passes from one medium to another medium is known as Refraction.
• It occurs because of the differences in density between the two substances.
• It is one of the most commonly seen phenomena, waves like sound waves and water waves also occurs due to refraction.
• It is possible for us to have optical instruments such as magnifying glasses, lenses and prisms because of Refraction.
• Thus, the correct answer among all the options is Refraction.

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