A ray of light is incident on a boundary between glass and air.
Under which conditions is the ray of light totally internally reflected?
The ray, initially in the air, is incident on the air–glass boundary at an angle of incidence greater than the critical angle.
The ray, initially in the glass, is incident on the glass–air boundary at an angle of incidence greater than the critical angle.
The ray, initially in the glass, is incident on the glass–air boundary at any angle of incidence.
The ray, initially in the air, is incident on the air–glass boundary at any angle of incidence.
100 exam-style questions on CIE IGCSE Physics 3.2.2 Refraction of light. Each one has a worked solution and a mark scheme showing where the marks go.