Refractive Index: Speed of Light in Medium vs Vacuum

[Sarrah]

Dear Sir/Madam, Is the product of the refractive index of a medium and speed of light in the medium equal to the speed of light in vacuum? Thank You.

 

[RPinPA]

Yes.

index of refraction is defined as $n = c_{vacuum} / c_{medium}$ so $c_{vacuum} = n c_{medium}$

 

[Sarrah]

Thank you so much sir.