Aspacecraft is traveling in interplanetary space at a constant velocity. what is the estimated distance traveled by the spacecraft in 9.50 seconds? a. 2.30 × 102 kilometers b. 2.42 × 102 kilometers c. 2.51 × 102 kilometers d. 3.02 × 102 kilometers

the answer is kevlar

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.

snell's law

refractve index = sin incidence / sin refraction

3. dark matter

empty space could also be a simple vacuum