A student investigates the refraction of a green laser beam as it passes from air into a rectangular block made of an optical polymer.
The student measures and records the angle of incidence, θi\theta_iθi, and the corresponding angle of refraction, θr\theta_rθr, for small angles.
Figure 1 is a graph of the student's results.
| Angle of refraction, θr\theta_rθr (degrees) | Angle of incidence, θi\theta_iθi (degrees) |
|---|---|
| 0 | 0 |
| 10 | 15 |
| 20 | 30 |
Use Figure 1 to calculate a value for:
θiθr \frac{\theta_i}{\theta_r} θrθi