A person wants to read a book placed at `20 cm`, whereas near point of his eye is `30 cm`. Calculate the power of the lens required.

A person wants to read a book placed at 20 cm whereas the near poit of his eyes is 50 cm. Calculate the power of the lens required.

The near point of a hypermetropic eye is 50 cm . Calculate the power of the lens to enable him to read a book at 40 cm ?

A person is unable to see objects nearer than 50 cm. He wants to read a book placed at a distance of 25 cm. Find the nature, focal length and power of the lens he requires for his spectacles.

The far point of a myopic person is 120 cm in front of the eye. Calculate the power of the lens required to enable the person see distant object clearly.

A person cannot see objects nearer than 1.2 m from his eyes. He wants for read a newspaper placed at a distance of 30 cm clearly. What is the nature and the power of lens required for this purpose?

A man, wearing glasses of power +2D can read clearly a book placed at a distance of 40cm from the eye. The power of the lens required so that he can read at 25cm from the eye is