A student cannot read properly from the blackboard while sitting on the front desk in a classroom of a big size. He however, can read clearly while sitting on the last desk of the classroom.
(a) Draw ray diagrams to illustrate the formation of image of’the blackboard writing by his eye lens when he is seated at the (i) front desk, (ii) last desk.
(b) Name the defect of the eye from which the student is suffering.
© Name the type of lens that would enable him to see the blackboard writing clearly, when seated on the front desk. Draw a ray diagram to illustrate how this lens helps him to see clearly.
(a) (i) Formation of image of blackboard writing by the eye lens of the student sitting on the front desk is as shown below.
(ii) Formation of the image of the blackboard writing by the eye lens of the student sitting on the last desk is shown below.
(b) The student is suffering from hypermetropia or long sightedness.
© His eye defect can be corrected by using a convex lens of suitable power as shown above.