A person use a spectancle of power of lens - 1.25 D.
What type of lens is this ?

A person use a spectancle of power of lens - 1.25 D. Find the focal length of the lens ?

It is written by the doctor for the eye lens as -2.50. What type of lens is it ?

The unit of focal power of a lens is___.

The nature of images formed by two lenses are given. What type of lens is used in each case An erect and diminished virtual image. .

The nature of images formed by two lenses are given. What type of lens is used in each case An erect and magnified virtual image. .

Define power of a lens. Write its S.I. unit