The Laws of Refraction of Light and Refractive Index (Leaving Cert Physics): Flashcards

Change in direction as light crosses boundary between media

Light travels at different speeds in different substances

Incident ray, normal, refracted ray all lie in same plane

Line perpendicular to surface at point of incidence

$\frac{\sin i}{\sin r} = n$

How much light slows down and bends entering a material

$n = \frac{c}{v}$ where $c$ = vacuum speed, $v$ = medium speed

1.33

2.42

1.0003 ≈ 1

$3 \times 10^8$ m/s

$n_{12} = \frac{n_2}{n_1}$

Bends toward the normal

Bends away from the normal

Slower light speed in that medium