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

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

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

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

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. .