Question

Which of the following statements is true for the rays shown in the figure below? ray 1 and ray 2 are possible only when n_B > n_A ray 4 and ray 5 are possible only when n_B < n_A ray 3 is possible only when n_A = n_B Briefly explain your answer to the previous question. A laser beam travels from medium A (index of refraction n_A) to medium B (index of refraction n_B). Which of the following statements could be true as the laser beam enters medium B? The frequency of the beam increases while the wavelength of the beam decreases. The velocity of propagation of the beam decreases and the frequency of the beam decreases. The velocity of propagation of the beam decreases and the wavelength of the beam decreases.

Answer 1

3)

Light not only bounces off from the surface it goes through some of it often slowing down and changing direction in the process called refraction. It occurs at the point where light travels from one medium to another of different density.

When a ray of light (i.e., the incident ray) goes from rarer to denser medium, the ray (refracted ray) bends towards the normal in the denser medium

and

If ray of light travels from denser to rarer medium the refracted ray bends away from the normal.

your marked answer is correct.

Total internal reflection is the phenomenon that involves the reflection of all the incident light off the boundary. TIR only takes place when both of the following two conditions are met:

1)the light is in the more dense medium and approaching the less dense medium.

2)the angle of incidence is greater than the so-called critical angle.\

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A laser beam travels from medium A to medium B

When we talk about the speed of light, we're usually talking about the speed of light in a vacuum, which is 3.00 x 10⁸ m/s. When light travels through something else, such as glass, diamond, or plastic, it travels at a different speed. The speed of light in a given material is related to a quantity called the index of refraction, n, which is defined as the ratio of the speed of light in vacuum to the speed of light in the medium:

index of refraction : n = c / v

When light travels from one medium to another, the speed changes, as does the wavelength. The index of refraction can also be stated in terms of wavelength:

where λ is the wave length in vacuum and λrn is the wave length in the medium.

Although the speed changes and wavelength changes, the frequency of the light will be constant. The frequency, wavelength, and speed are related by:

note you can also refer snells law