Which of the following statements is false of total internal reflection (TIR) ?

(1) When TIR occurs, the reflected light obeys the law of reflection.

(2) If TIR occurs at the boundary of water and air, then the light must be within water and heading towards the boundary with air.

(3) TIR causes a portion of the light to be refracted and the rest to be reflected.

(4) TIR only occurs when the angle of incidence is greater than the critical angle.

(3) TIR causes a portion of the light to be refracted and the rest to be reflected

Explanation:

Total internal reflection is the reflection of a light ray completely within a medium for example glass or water which bounces back after reflecting from the surrounding surfaces into the medium. When the incident angle is more than an certain limiting angle, called the critical angle, the phenomenon is called total internal reflection.

In total internal reflection none of the portion of the incident light gets refracted, it gets only reflected multiple times within the medium.

Hence the false statement is (3).