NEETPhysicsGeometrical OpticsMCQ+4 / −1
An object is mounted on a wall. Its image of equal size is to be obtained on a parallel wall with the help of a convex lens placed between these walls. The lens is kept at distance x in front of the second wall. The required focal length of the lens will be :
- Aless than
- Bmore than but less than
- C
- D
View written solutionFree
Correct answer: C

$\mathrm{x=2f}$
$\mathrm{f=x/2}$
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