A ray of light is incident on a material with reflective indeed n=1.46. if the material has thickness w=2.6mm; how many times does the light take to pass through the material?
To determine how many times the light ray passes through the material, we need to consider the reflection of the ray at each boundary.
When light passes from one medium to another with a different refractive index, some of the light is reflected and some is transmitted. The transmitted light will continue to propagate through the material.
In this case, the light is incident on a material with a refractive index of 1.46. If the light ray is incident perpendicular to the surface (normal incidence), all the light will be transmitted and none will be reflected.
Therefore, the light ray will pass through the material once without any reflection, regardless of the thickness of the material.
Hence, the light takes only one passage through the material.