The diagram represents a thin beam of light striking a glass-air boundary. Part of the light travels out along the glass surface and part of it is reflected back into the glass. Which row is correct?
- Athis is an example of total internal reflection: no; angle $\theta$ is the critical angle: yes
- Bthis is an example of total internal reflection: no; angle $\theta$ is the critical angle: no
- Cthis is an example of total internal reflection: yes; angle $\theta$ is the critical angle: no
- Dthis is an example of total internal reflection: yes; angle $\theta$ is the critical angle: yes