Question

A transparent plastic has been developed. When light travels through it, it only travels at 3 × 107 m/s. What will be the refractive index of this new plastic?

Answer 1

$n = \frac{c}{v}$

$v = 3*10^7 \frac{m}{s}$

$c\approx 3*10^8\frac{m}{s}$

$n = \frac {3*10^8}{3*10^7}= 10$

$\text{Answer: the refractive index n = 10}$