At C the ray of light is incident again along the normal and passes straight through into air without being bent. The critical angle for the type of glass used to make the prism = 42 o.

In contrast to the "acceptance angle," which is measured outside the fiber, the critical angle is a measurement within the fiber. See numerical aperture. THIS DEFINITION IS FOR PERSONAL USE ONLY.

Mathematicians used physics models and gymnasium experiments to understand why and pinpointed a specific “critical angle” of the crowd’s movement—13 degrees—to explain why crowded ...

Mathematicians used physics models and gymnasium experiments to understand why and pinpointed a specific “critical angle” of the crowd’s movement—13 degrees—to explain why crowded ...

Schematic of a grazing incidence small and wide angle X-ray scattering (GISAXS/GIWAXS) experimental setup showing the incident (αi ... typically below the critical angle for total external reflection.