An object is gradually moved along the principal axis of a thin convex lens from a…
PHYSICS · Subjective · CBSE · Physics · Light — Reflection and Refraction · Light — Reflection and Refraction
Problem
An object is gradually moved along the principal axis of a thin convex lens from a point far beyond 2F to just inside the focal length.
(i) Describe qualitatively how the position of the image changes in relation to the lens as the object passes through the following regions:
(a) far beyond 2F,
(b) just beyond 2F,
(c) between 2F and F,
(d) at F,
(e) between F and the optical centre.
(ii) State the nature (real/virtual, erect/inverted) and relative size (diminished, same size, enlarged) of the image in each of the above regions.
(iii) Using labelled sketches, explain why the image characteristics change in the manner stated in parts (i) and (ii).