A boy who is suffering from eye defect has been given a prescription a

1.	A boy who is suffering from eye defect has been given a prescription as -2D. Based on the information given, answer the following questions. a) Identify the eye defect he is suffering. b) Write the nature and focal length of the lens.
Answer» a) The boy is suffering from myopia. b) Nature of the lens : The lens is biconcave lens. It is thin at the middle and thicker at the edges. Focal length of the lens : Given that power is – 2D P = 100/f (in cm) (or) f = 100/P = 100/-2 = - 50 cm Focal length (f) = -50 cm

A boy who is suffering from eye defect has been given a prescription as -2D. Based on the information given, answer the following questions. a) Identify the eye defect he is suffering. b) Write the nature and focal length of the lens.

Answer»

a) The boy is suffering from myopia.

b) Nature of the lens :

The lens is biconcave lens. It is thin at the middle and thicker at the edges.

Focal length of the lens :

Given that power is – 2D

P = 100/f (in cm)

(or) f = 100/P = 100/-2 = - 50 cm

Focal length (f) = -50 cm