If the image formed by a lens for all positions of an object placed in front of it is always
Channel: Doubtnut
Date: 2020-07-26

If the image formed by a lens for all positions of an object placed in front of it is always erect and diminished, what is the nature of this lens ? Draw a ray diagram to justify your answer. If the numerical value of power of this lens is 10 D, what is its focal length in cartesian system ?