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SAI INTERNATIONAL SCHOOL
                                                       Class 7
                                                   Lesson Notes
                                                 Subject-Physics
                                  CH: Light and Associated Phenomena
                                   Subtopic- Human eye and Dispersion


              HUMAN EYE:
               It is a natural optical organ with the help of which a person can see objects around him.


              PARTS OF HUMAN EYE:
                        Cornea
                        Iris
                        Pupil
                        Eye lens
                        Cilliary muscles
                        Retina
                        Optic nerve


              CONSTRUCTION OF HUMAN EYE:
              Light enters the eye through cornea. Behind the cornea, there are iris, pupil and eye lens. The
              retina is present behind the eye lens, which acts as a screen on which the image is formed.































             IMAGE FORMATION IN THE EYE:
                (i)  When light rays enter into the eye through cornea, fall on the eye lens.
                (ii) The eye lens focuses the light rays to form real and inverted image on the retina which
                    acts as a screen.
                (iii) The retina is connected to the optic nerve which carries the image (real and inverted)
                    formed on the retina to the brain in the form of electrical signals.
                (iv) Brain interprets the information and forms a real and erect image of the object with the
                    correct size.
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