Optics Question 696
Question: The plane faces of two identical plano-convex lenses each having focal length of 40 cm are pressed against each other to form a usual convex lens. The distance from this lens, at which an object must be placed to obtain a real, inverted image with magnification one is
[NCERT 1980; CPMT 1981; MP PMT 1999; UPSEAT 1999]
Options:
A) 80 cm
B) 40 cm
C) 20 cm
D) 162 cm
Show Answer
Answer:
Correct Answer: B
Solution:
To obtain, an inverted and equal size image, object must be paced at a distance of 2f from lens, i.e. 40 cm in this case.
