Question

Calculate the speed of light in sapphire

Answer 1

 sapphire refractive index is 1.77
speed = 3*10^8/1.77
           =1.69*10^8

Answer 2

Answer:

The refractive index of sapphire = 1.71.

The speed of light in vaccum = 3 x $10^{8}$ m/s.

Refractive index = speed of light in vaccum / speed of light in sapphire.

1.71 = 3 x $10^{8}$ / $c_{2}$.

$c_{2}$ = 3 x $10^{8}$ / 1.71.

$c_{2}$ = 1.75 x $10^{8}$ m/s.

∴ The speed of light in sapphire = 1.75 x $10^{8}$ m/s.