Physics for IGCSE & O level - Rays And Waves (Section 11 - No. 17)
What is the main purpose of the iris in the eye?
To focus light onto the retina.
To control the amount of light entering the eye.
To produce tear fluid.
To protect the eye from damage.
Selitys
The iris controls the amount of light entering the eye by adjusting the size of the pupil.