A 40-year-old professor requires eyeglasses with lenses of 2D power to read a book at 25cm. What is his near point?

A certain myopic person has a far point of 150 cm. If he is able to read a book at 25 cm, while wearing the glasses, is his near point less than 25 cm. ?

Kumar’s near point is 40 cm.Find the nature and power of lens which would enable him to read a book placed at 20 cm from his eyes.

Ram’s near point is 50 cm. Find the nature and power of lens which would enable him to read a book placed at 25 cm from his eyes.

Two lenses of power +12 D and -2D are combined together.What is their equivalent focal length?