Question

"the refractive index of diamond is 2. 42". what is the meaning of this statement in relation to the speed of light? 1)minimum 2)maximum?

Answer 1

This means that the ratio of speed of light in air or vacuum to the speed of light in diamond is 2.42.

Mew = Speed of light in air/Speed of light in diamond

or 2.42 = 3 x 10^8 / y
or. y = 1.23x10^8 m/s
Hence speed of light in diamond is less than that in air

Answer 2

Refractive Index shows the comparison of light speeds in two mediums. Light may travel from rarer to denser medium or from denser to rarer medium. When we say refractive index of diamond is 2.42, it means light is travelling from rarer to denser medium, and speed of light in air(vacuum) is 2.42 times the speed of light in diamond. On the other hand if the light travels from denser to rarer medium, that is, from diamond to air the refractive index will be 1/2.42.............  ## Hope it helps you ......