The power of a lens is –0.25 D. Based on this information, find out (a) The type of lens and its focal…
The power of a lens is –0.25 D. Based on this information, find out
(a) The type of lens and its focal length.
(b) The eye defect for which it may be used as a corrective lens.
(c) The nature and size of the image formed by this lens when an object is placed between F and 2F from the optical centre of this lens.
Solution
(a) Concave lens
P = $\dfrac{1}{f}$(m) → f = 1/-0.25 → f = -4 m
(b) Myopia
(c) Virtual, Erect
Diminished