About This Lesson
This animation shows how light behaves when it travels from glass to air. When the angle of incidence in glass is
most of the light refracts and leaves the glass. However when the angle of incidence is 42 or more ALL the light is reflected back inside the glass.
This is called and the angle at which this happens the
for the glass.
Notice that when the angle of incidence is less than the critical angle
of the light is reflected back inside the glass.