Question

1. when does total internal reflection occur? (1 point)

when the angle of incidence exceeds the critical angle
when the angle of incidence exceeds the angle of reflection
when the angle of incidence is less than the critical angle
when the angle of incidence is less than the angle of reflection

Explanation:

Total internal reflection occurs when light travels from a medium with a higher refractive index to one with a lower refractive index. The critical angle is the angle of incidence at which the refracted angle is \(90^{\circ}\). When the angle of incidence exceeds the critical angle, all the light is reflected back into the original medium (total internal reflection). The law of reflection states that the angle of incidence equals the angle of reflection (\(\theta_i=\theta_r\)), so options involving the angle of incidence exceeding or being less than the angle of reflection are incorrect. If the angle of incidence is less than the critical angle, refraction (not total internal reflection) occurs.

Answer:

when the angle of incidence exceeds the critical angle