Describe the functioning of the periscope. Also, tell that how many mirrors are there in a periscope.

Name any one defect of the eye. How is it corrected?

Briefly explain the term persistence of vision.

Explain lateral inversion with an example.

What do you mean by sources of light?

What are the functions of the optic nerve and retina?

Draw a diagram of the human eye.

Briefly mention which of the following will cause regular reflection of light and which diffuse reflection of light

(a) Polished wooden table   (b) Chalk powder   (c) Cardboard

(d) Mirror                              (e) Paper                (f) Marble floor with water spread over it