critical angle (redirected from critical angles)

critical angle

n.

1. The smallest angle of incidence at which a light ray passing from one medium to another less refractive medium can be totally reflected from the boundary between the two.

2. The angle of attack of an airfoil at which airflow abruptly changes, causing changes in the lift and drag of an aircraft.

---

critical angle  (krt-kl)

The smallest angle of incidence at which radiation, such as light, is completely reflected from the boundary between two media. At angles smaller than the critical angle, some of the radiation enters the second material and is refracted.

Thesaurus

Noun

1.

critical angle - the smallest angle of incidence for which light is totally reflected angle of incidence, incidence angle - the angle that a line makes with a line perpendicular to the surface at the point of incidence