For a concave lens of focal length f, the relation between object and image distances u and is v, respectively, from its pole can best be represented by ( u−v is the reference line):
(A)(see structure)
(B)(see structure)✓ Correct
(C)(see structure)
(D)(see structure)
Answer: (B)
Solution
For a diverging lens the image of any real object is virtual, erect and nearer the lens than the object, so ∣v∣<∣u∣ throughout and the image stays on the same side as the object. Writing v1−u1=f1 with f<0, as the object recedes from the pole to infinity the image moves out only as far as the focus, v→f, never beyond it. The curve that keeps the image distance smaller in magnitude than the object distance and approaches the focal length asymptotically is the one that represents this relation.
JEE Main · 2020 · 05 Sep 2020 · Shift 1 · Single correct option