Asmall mirror is attached to a vertical wall, and it hangs a distance of 1.70 m above the floor. the mirror is facing due east, and a ray of sunlight strikes the mirror early in the morning and then again later in the morning. the incident and reflected rays both lie in a plane that is perpendicular to both the wall and the floor. early in the morning, the ray is observed to strike the floor at a distance of 3.75 m from the base of the wall. later on in the morning, the ray strikes the floor at a distance of 1.18 m from the wall. the earth rotates at 15.0 degrees per hour. how much time (in hours) has elapsed between the two observations

im guessing the west of station b

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.