question_answer

A point object is placed on the optic axis of a convex lens of focal length\[f\]at a distance of \[2f\]to the left of it. The diameter of the lens is d. An eye is placed at a distance of \[3f\] to the right of the lens and a distance h below the optic axis. The maximum value of h to see the image is

A)  \[\frac{d}{2}\]                                   

B) \[d\]                 

C)       \[\frac{d}{4}\]                       

D)       \[\frac{d}{3}\]

Correct Answer: C

Solution :

As is clear from the figure that triangles ACI and EBI are similar. Using similarity rule, we get \[\therefore \]\[\frac{h}{d/2}=\frac{f}{2f},\]where \[h=BE\] \[\Rightarrow \]\[\frac{2h}{d}=\frac{1}{2}\]or \[h=d/4\] Hence, the correction option is (c).