Regarding the refractive index of an ordinary transparent material medium, relative to air, which statement is correct?

Please wait…

1. Regarding the refractive index of an ordinary transparent material medium, relative to air, which statement is correct?

It can be either positive or negative

It can have a value of zero

It is exactly 1 for every material

It is always greater than 1

 Loading…

 

Since ordinary transparent materials, like glass or water, slow light down compared to air, their refractive index relative to air is always greater than 1.