Question

light travels a distance of 0.902 m in 4 ns in a given substance. what is the index of refraction of this substance?

Answer 1

Speed of light in substance
= distance / time
= 0.902 / (4 x 10^-9)
= 2.255 x 10^8

Index of refraction
= speed of light in vacuum / speed of light in substance
= 3 x 10^8 / (2.255 x 10^8)
= 1.33