A man suffering from myopia can read book placed at `10 cm` distance. For reading the book at a distance of `60 cm` with relaxed vision, focal length of the lens required will be

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.

When an object is placed at a distance 6 cm from a concave lens a virtual image is formed at a distance 4cm from it. Find the focal length of the lens.

An object is placed at a distance of 15 cm from a convex lens.If the focal length of the lens is 60cm,find the image distance.

A man uses spectacles of a concave lens for his defective eye and can read a book placed at a distance of 25 cm from him. The focal length of the lens of the spectacles is 50 cm . At what distance should the book be kept if he wants to read it without spectacles ?

An object is placed at a distance of 15 cm from a convex lens. If the focal length of the lens is 60 cm, find the image distance.

A shortsighted man can read the writings of a book keeping it at a distance of 15 cm from his eyes. To read the book placed at a distance of 60 cm from his eyes what type of spectacles should he use ? What will be the power of the spectacles ?